diff --git a/data/gui.xml b/data/gui.xml
index 4fdf1a658..530692b97 100644
--- a/data/gui.xml
+++ b/data/gui.xml
@@ -636,6 +636,7 @@
         <separator id="scripts_menu_separator" />
         <menu id="scripts_menu" text="@.file_scripts" group="file_scripts">
           <item command="OpenScriptFolder" text="@.file_open_script_folder" />
+          <item command="Refresh" text="@.file_rescan_script_folder" />
         </menu>
         <separator group="file_app" />
         <item command="Exit" text="@.file_exit" />
diff --git a/data/pref.xml b/data/pref.xml
index a18597331..b2534bd03 100644
--- a/data/pref.xml
+++ b/data/pref.xml
@@ -28,6 +28,8 @@
       <value id="NONE" value="0" />
       <value id="EDGES" value="1" />
       <value id="FULL" value="2" />
+      <value id="FULLALL" value="3" />
+      <value id="FULLNEDGES" value="4" />
     </enum>
     <enum id="BgType">
       <value id="CHECKED_16x16" value="0" />
diff --git a/data/strings/en.ini b/data/strings/en.ini
index 49f2431c4..b32213bea 100644
--- a/data/strings/en.ini
+++ b/data/strings/en.ini
@@ -806,6 +806,7 @@ file_export_sprite_sheet = &Export Sprite Sheet
 file_repeat_last_export = Repeat &Last Export
 file_scripts = Scri&pts
 file_open_script_folder = &Open Scripts Folder
+file_rescan_script_folder = &Rescan Scripts Folder
 file_exit = E&xit
 edit = &Edit
 edit_undo = &Undo
@@ -1185,8 +1186,10 @@ simple_crosshair = Simple Crosshair
 crosshair_on_sprite = Crosshair on Sprite
 brush_preview = Brush Preview:
 brush_preview_none = None
-brush_preview_edges = Brush Edges
-brush_preview_full = Full Real-time Brush Preview
+brush_preview_edges = Edges Only
+brush_preview_full = Full Preview
+brush_preview_fullall = Full Preview with All Tools
+brush_preview_fullnedges = Full Preview and Edges
 cursor_color_type = Crosshair && Brush Edges Color:
 cursor_neg_bw = Negative Black and White
 cursor_specific_color = Specific Color
diff --git a/data/widgets/options.xml b/data/widgets/options.xml
index c606d86d8..cb51d04a0 100644
--- a/data/widgets/options.xml
+++ b/data/widgets/options.xml
@@ -292,6 +292,8 @@
               <listitem text="@.brush_preview_none" value="0" />
               <listitem text="@.brush_preview_edges" value="1" />
               <listitem text="@.brush_preview_full" value="2" />
+              <listitem text="@.brush_preview_fullall" value="3" />
+              <listitem text="@.brush_preview_fullnedges" value="4" />
             </combobox>
 
 	    <label text="@.cursor_color_type" />
diff --git a/laf b/laf
index ab08b047d..c6a00f92f 160000
--- a/laf
+++ b/laf
@@ -1 +1 @@
-Subproject commit ab08b047defdd3390e3aaa55a02c6a10225496ac
+Subproject commit c6a00f92ff4f073864db99e48c415997381cd88a
diff --git a/src/app/cmd/add_cel.cpp b/src/app/cmd/add_cel.cpp
index e6a3c0813..d34d800ef 100644
--- a/src/app/cmd/add_cel.cpp
+++ b/src/app/cmd/add_cel.cpp
@@ -1,4 +1,5 @@
 // Aseprite
+// Copyright (C) 2020  Igara Studio S.A.
 // Copyright (C) 2001-2018  David Capello
 //
 // This program is distributed under the terms of
@@ -108,10 +109,13 @@ void AddCel::removeCel(Layer* layer, Cel* cel)
   ev.sprite(layer->sprite());
   ev.layer(layer);
   ev.cel(cel);
-  doc->notify_observers<DocEvent&>(&DocObserver::onRemoveCel, ev);
+  doc->notify_observers<DocEvent&>(&DocObserver::onBeforeRemoveCel, ev);
 
   static_cast<LayerImage*>(layer)->removeCel(cel);
   layer->incrementVersion();
+
+  doc->notify_observers<DocEvent&>(&DocObserver::onAfterRemoveCel, ev);
+
   delete cel;
 }
 
diff --git a/src/app/commands/cmd_cel_properties.cpp b/src/app/commands/cmd_cel_properties.cpp
index 43a7e60b7..1c976e593 100644
--- a/src/app/commands/cmd_cel_properties.cpp
+++ b/src/app/commands/cmd_cel_properties.cpp
@@ -230,6 +230,11 @@ private:
   }
 
   // DocObserver impl
+  void onBeforeRemoveCel(DocEvent& ev) override {
+    if (m_cel == ev.cel())
+      setCel(m_document, nullptr);
+  }
+
   void onCelOpacityChange(DocEvent& ev) override {
     if (m_cel == ev.cel())
       updateFromCel();
diff --git a/src/app/commands/cmd_refresh.cpp b/src/app/commands/cmd_refresh.cpp
index a58b31732..31596469b 100644
--- a/src/app/commands/cmd_refresh.cpp
+++ b/src/app/commands/cmd_refresh.cpp
@@ -10,7 +10,10 @@
 #endif
 
 #include "app/app.h"
+#include "app/app_menus.h"
 #include "app/commands/command.h"
+#include "app/ui/main_menu_bar.h"
+#include "app/ui/main_window.h"
 #include "app/ui/status_bar.h"
 #include "fmt/format.h"
 #include "ui/scale.h"
@@ -40,8 +43,15 @@ RefreshCommand::RefreshCommand()
 
 void RefreshCommand::onExecute(Context* context)
 {
+  // Reload menus (mainly to reload the File > Scripts menu)
+  //AppMenus::instance()->reload();
+  App::instance()->mainWindow()->getMenuBar()->reload();
+
+  // Reload theme
   ui::set_theme(ui::get_theme(),
                 ui::guiscale());
+
+  // Redraw screen
   app_refresh_screen();
 
   // Print memory information
diff --git a/src/app/commands/command.cpp b/src/app/commands/command.cpp
index 0764b383f..4ac363209 100644
--- a/src/app/commands/command.cpp
+++ b/src/app/commands/command.cpp
@@ -1,4 +1,5 @@
 // Aseprite
+// Copyright (C) 2020  Igara Studio S.A.
 // Copyright (C) 2001-2017  David Capello
 //
 // This program is distributed under the terms of
@@ -21,7 +22,10 @@ Command::Command(const char* id, CommandFlags flags)
 {
   std::string strId = "commands.";
   strId += this->id();
-  m_friendlyName = Strings::instance()->translate(strId.c_str());
+  if (auto s = Strings::instance())
+    m_friendlyName = s->translate(strId.c_str());
+  else
+    m_friendlyName = strId;
 }
 
 Command::~Command()
diff --git a/src/app/commands/new_params.cpp b/src/app/commands/new_params.cpp
index b7567f935..a7f8be407 100644
--- a/src/app/commands/new_params.cpp
+++ b/src/app/commands/new_params.cpp
@@ -357,7 +357,7 @@ void Param<filters::ColorCurve>::fromLua(lua_State* L, int index)
 template<>
 void Param<tools::InkType>::fromLua(lua_State* L, int index)
 {
-  script::get_value_from_lua<tools::InkType>(L, index);
+  setValue(script::get_value_from_lua<tools::InkType>(L, index));
 }
 
 template<>
diff --git a/src/app/context.cpp b/src/app/context.cpp
index 3a62da3e7..078dd9126 100644
--- a/src/app/context.cpp
+++ b/src/app/context.cpp
@@ -148,7 +148,11 @@ void Context::executeCommand(Command* command, const Params& params)
   try {
     m_flags.update(this);
 
+#if 0
+    // params.empty() can be empty when we call the command from Lua
+    // with a table.
     ASSERT(!command->needsParams() || !params.empty());
+#endif
 
     command->loadParams(params);
 
diff --git a/src/app/doc_observer.h b/src/app/doc_observer.h
index 904c40812..7c958c120 100644
--- a/src/app/doc_observer.h
+++ b/src/app/doc_observer.h
@@ -40,7 +40,8 @@ namespace app {
     // removed, and the sprite's total number of frames is modified.
     virtual void onRemoveFrame(DocEvent& ev) { }
     virtual void onRemoveTag(DocEvent& ev) { }
-    virtual void onRemoveCel(DocEvent& ev) { }
+    virtual void onBeforeRemoveCel(DocEvent& ev) { }
+    virtual void onAfterRemoveCel(DocEvent& ev) { }
     virtual void onRemoveSlice(DocEvent& ev) { }
 
     virtual void onSpriteSizeChanged(DocEvent& ev) { }
diff --git a/src/app/tools/controllers.h b/src/app/tools/controllers.h
index 777ab73a3..4b5bb1dda 100644
--- a/src/app/tools/controllers.h
+++ b/src/app/tools/controllers.h
@@ -153,6 +153,8 @@ public:
     stroke[0] = m_first;
     stroke[1] = pt;
 
+    bool isoAngle = false;
+
     if ((int(loop->getModifiers()) & int(ToolLoopModifiers::kSquareAspect))) {
       int dx = stroke[1].x - m_first.x;
       int dy = stroke[1].y - m_first.y;
@@ -173,6 +175,7 @@ public:
         else if (angle < 36.0) {
           stroke[1].x = m_first.x + SGN(dx)*maxsize;
           stroke[1].y = m_first.y + SGN(dy)*maxsize/2;
+          isoAngle = true;
         }
         // Snap at 45
         else if (angle < 54.0) {
@@ -183,6 +186,7 @@ public:
         else if (angle < 72.0) {
           stroke[1].x = m_first.x + SGN(dx)*maxsize/2;
           stroke[1].y = m_first.y + SGN(dy)*maxsize;
+          isoAngle = true;
         }
         // Snap vertically
         else {
@@ -207,8 +211,8 @@ public:
     else if ((int(loop->getModifiers()) & int(ToolLoopModifiers::kFromCenter))) {
       int rx = stroke[1].x - m_first.x;
       int ry = stroke[1].y - m_first.y;
-      stroke[0].x = m_first.x - rx;
-      stroke[0].y = m_first.y - ry;
+      stroke[0].x = m_first.x - rx + (isoAngle && ABS(rx) > ABS(ry) ? SGN(rx)*(rx & 1): 0);
+      stroke[0].y = m_first.y - ry + (isoAngle && ABS(rx) < ABS(ry) ? SGN(ry)*(ry & 1): 0);
       stroke[1].x = m_first.x + rx;
       stroke[1].y = m_first.y + ry;
     }
diff --git a/src/app/tools/intertwine.cpp b/src/app/tools/intertwine.cpp
index 0e963e6b2..e4d9f6042 100644
--- a/src/app/tools/intertwine.cpp
+++ b/src/app/tools/intertwine.cpp
@@ -127,7 +127,8 @@ doc::AlgoLineWithAlgoPixel Intertwine::getLineAlgo(ToolLoop* loop,
                                                    const Stroke::Pt& b)
 {
   bool needsFixForLineBrush = false;
-  if (loop->getBrush()->type() == kLineBrushType) {
+  if ((loop->getBrush()->type() == kLineBrushType) &&
+      (a.size > 1.0 || b.size > 1.0)) {
     if ((a.angle != 0.0f || b.angle != 0.0f) &&
         (a.angle != b.angle)) {
       needsFixForLineBrush = true;
diff --git a/src/app/ui/doc_view.cpp b/src/app/ui/doc_view.cpp
index bdfe24b57..27418219f 100644
--- a/src/app/ui/doc_view.cpp
+++ b/src/app/ui/doc_view.cpp
@@ -428,7 +428,7 @@ void DocView::onAddCel(DocEvent& ev)
   UIContext::instance()->notifyActiveSiteChanged();
 }
 
-void DocView::onRemoveCel(DocEvent& ev)
+void DocView::onAfterRemoveCel(DocEvent& ev)
 {
   // This can happen when we apply a filter that clear the whole cel
   // and then the cel is removed in a background/job
diff --git a/src/app/ui/doc_view.h b/src/app/ui/doc_view.h
index 14b8507ab..ad4d7b370 100644
--- a/src/app/ui/doc_view.h
+++ b/src/app/ui/doc_view.h
@@ -78,7 +78,7 @@ namespace app {
     void onRemoveFrame(DocEvent& ev) override;
     void onTagChange(DocEvent& ev) override;
     void onAddCel(DocEvent& ev) override;
-    void onRemoveCel(DocEvent& ev) override;
+    void onAfterRemoveCel(DocEvent& ev) override;
     void onTotalFramesChanged(DocEvent& ev) override;
     void onLayerRestacked(DocEvent& ev) override;
 
diff --git a/src/app/ui/editor/brush_preview.cpp b/src/app/ui/editor/brush_preview.cpp
index 51f493694..267a58467 100644
--- a/src/app/ui/editor/brush_preview.cpp
+++ b/src/app/ui/editor/brush_preview.cpp
@@ -149,7 +149,7 @@ void BrushPreview::show(const gfx::Point& screenPos)
      (ink->isEffect()) ||
      // or when the brush color is transparent and we are not in the background layer
      (!ink->isShading() &&
-      (layer && !layer->isBackground()) &&
+      (layer && layer->isTransparent()) &&
       ((sprite->pixelFormat() == IMAGE_INDEXED && brush_color == mask_index) ||
        (sprite->pixelFormat() == IMAGE_RGB && rgba_geta(brush_color) == 0) ||
        (sprite->pixelFormat() == IMAGE_GRAYSCALE && graya_geta(brush_color) == 0))))) {
@@ -160,6 +160,8 @@ void BrushPreview::show(const gfx::Point& screenPos)
   }
 
   bool showPreview = false;
+  bool showPreviewWithEdges = false;
+  bool cancelEdges = false;
   auto brushPreview = pref.cursor.brushPreview();
   if (!m_editor->docPref().show.brushPreview())
     brushPreview = app::gen::BrushPreview::NONE;
@@ -172,7 +174,20 @@ void BrushPreview::show(const gfx::Point& screenPos)
       m_type = BRUSH_BOUNDARIES;
       break;
     case app::gen::BrushPreview::FULL:
+    case app::gen::BrushPreview::FULLALL:
+    case app::gen::BrushPreview::FULLNEDGES:
       showPreview = m_editor->getState()->requireBrushPreview();
+      switch (brushPreview) {
+        case app::gen::BrushPreview::FULLALL:
+          if (showPreview)
+            m_type = CROSSHAIR;
+          cancelEdges = true;
+          break;
+        case app::gen::BrushPreview::FULLNEDGES:
+          if (showPreview)
+            showPreviewWithEdges = true;
+          break;
+      }
       break;
   }
 
@@ -183,6 +198,8 @@ void BrushPreview::show(const gfx::Point& screenPos)
   // layer) we don't show the brush preview temporally.
   if (showPreview && m_editor->isExtraCelLocked()) {
     showPreview = false;
+    showPreviewWithEdges = false;
+    cancelEdges = false;
     m_type |= BRUSH_BOUNDARIES;
   }
 
@@ -195,9 +212,12 @@ void BrushPreview::show(const gfx::Point& screenPos)
   // For cursor type 'bounds' we have to generate cursor boundaries
   if (m_type & BRUSH_BOUNDARIES) {
     if (brush->type() != kImageBrushType)
-      showPreview = false;
-    generateBoundaries();
+      showPreview = showPreviewWithEdges;
+    if (cancelEdges)
+      m_type &= ~BRUSH_BOUNDARIES;
   }
+  if (m_type & BRUSH_BOUNDARIES)
+    generateBoundaries();
 
   // Draw pixel/brush preview
   if (showPreview) {
diff --git a/src/app/ui/editor/editor.cpp b/src/app/ui/editor/editor.cpp
index e9ac060ce..e30240d9c 100644
--- a/src/app/ui/editor/editor.cpp
+++ b/src/app/ui/editor/editor.cpp
@@ -159,6 +159,7 @@ Editor::Editor(Doc* document, EditorFlags flags)
   , m_aniSpeed(1.0)
   , m_isPlaying(false)
   , m_showGuidesThisCel(nullptr)
+  , m_showAutoCelGuides(false)
   , m_tagFocusBand(-1)
 {
   if (!m_renderEngine)
@@ -875,8 +876,7 @@ void Editor::drawSpriteUnclippedRect(ui::Graphics* g, const gfx::Rect& _rc)
   }
 
   // Draw active layer/cel edges
-  bool showGuidesThisCel = this->showAutoCelGuides();
-  if ((m_docPref.show.layerEdges() || showGuidesThisCel) &&
+  if ((m_docPref.show.layerEdges() || m_showAutoCelGuides) &&
       // Show layer edges only on "standby" like states where brush
       // preview is shown (e.g. with this we avoid to showing the
       // edges in states like DrawingState, etc.).
@@ -887,9 +887,10 @@ void Editor::drawSpriteUnclippedRect(ui::Graphics* g, const gfx::Rect& _rc)
         g, cel,
         color_utils::color_for_ui(Preferences::instance().guides.layerEdgesColor()));
 
-      if (showGuidesThisCel &&
-          m_showGuidesThisCel != cel)
+      if (m_showAutoCelGuides &&
+          m_showGuidesThisCel != cel) {
         drawCelGuides(g, cel, m_showGuidesThisCel);
+      }
     }
   }
 
@@ -1764,6 +1765,9 @@ bool Editor::onProcessMessage(Message* msg)
     case kMouseLeaveMessage:
       m_brushPreview.hide();
       StatusBar::instance()->showDefaultText();
+
+      // Hide autoguides
+      updateAutoCelGuides(nullptr);
       break;
 
     case kMouseDownMessage:
@@ -2149,7 +2153,7 @@ void Editor::onBeforeRemoveLayer(DocEvent& ev)
     setLayer(layerToSelect);
 }
 
-void Editor::onRemoveCel(DocEvent& ev)
+void Editor::onBeforeRemoveCel(DocEvent& ev)
 {
   m_showGuidesThisCel = nullptr;
 }
@@ -2774,22 +2778,21 @@ void Editor::invalidateIfActive()
     invalidate();
 }
 
-bool Editor::showAutoCelGuides()
-{
-  return
-    (getCurrentEditorInk()->isCelMovement() &&
-     m_docPref.show.autoGuides() &&
-     m_customizationDelegate &&
-     int(m_customizationDelegate->getPressedKeyAction(KeyContext::MoveTool) & KeyAction::AutoSelectLayer));
-}
-
 void Editor::updateAutoCelGuides(ui::Message* msg)
 {
   Cel* oldShowGuidesThisCel = m_showGuidesThisCel;
+  bool oldShowAutoCelGuides = m_showAutoCelGuides;
+
+  m_showAutoCelGuides = (
+    msg &&
+    getCurrentEditorInk()->isCelMovement() &&
+    m_docPref.show.autoGuides() &&
+    m_customizationDelegate &&
+    int(m_customizationDelegate->getPressedKeyAction(KeyContext::MoveTool) & KeyAction::AutoSelectLayer));
 
   // Check if the user is pressing the Ctrl or Cmd key on move
   // tool to show automatic guides.
-  if (showAutoCelGuides() &&
+  if (m_showAutoCelGuides &&
       m_state->requireBrushPreview()) {
     ui::MouseMessage* mouseMsg = dynamic_cast<ui::MouseMessage*>(msg);
 
@@ -2805,8 +2808,10 @@ void Editor::updateAutoCelGuides(ui::Message* msg)
     m_showGuidesThisCel = nullptr;
   }
 
-  if (m_showGuidesThisCel != oldShowGuidesThisCel)
+  if (m_showGuidesThisCel != oldShowGuidesThisCel ||
+      m_showAutoCelGuides != oldShowAutoCelGuides) {
     invalidate();
+  }
 }
 
 // static
diff --git a/src/app/ui/editor/editor.h b/src/app/ui/editor/editor.h
index e999319b6..33fc7acfb 100644
--- a/src/app/ui/editor/editor.h
+++ b/src/app/ui/editor/editor.h
@@ -320,7 +320,7 @@ namespace app {
     void onExposeSpritePixels(DocEvent& ev) override;
     void onSpritePixelRatioChanged(DocEvent& ev) override;
     void onBeforeRemoveLayer(DocEvent& ev) override;
-    void onRemoveCel(DocEvent& ev) override;
+    void onBeforeRemoveCel(DocEvent& ev) override;
     void onAddTag(DocEvent& ev) override;
     void onRemoveTag(DocEvent& ev) override;
     void onRemoveSlice(DocEvent& ev) override;
@@ -436,6 +436,7 @@ namespace app {
     // The Cel that is above the mouse if the Ctrl (or Cmd) key is
     // pressed (move key).
     Cel* m_showGuidesThisCel;
+    bool m_showAutoCelGuides;
 
     // Focused tag band. Used by the Timeline to save/restore the
     // focused tag band for each sprite/editor.
diff --git a/src/app/ui/editor/moving_pixels_state.cpp b/src/app/ui/editor/moving_pixels_state.cpp
index 59ecb6a83..d6b7f6da6 100644
--- a/src/app/ui/editor/moving_pixels_state.cpp
+++ b/src/app/ui/editor/moving_pixels_state.cpp
@@ -5,6 +5,8 @@
 // This program is distributed under the terms of
 // the End-User License Agreement for Aseprite.
 
+#define MOVPIXS_TRACE(...) // TRACE(__VA_ARGS__)
+
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
@@ -174,7 +176,7 @@ void MovingPixelsState::onEditorGotFocus(Editor* editor)
 
 EditorState::LeaveAction MovingPixelsState::onLeaveState(Editor* editor, EditorState* newState)
 {
-  TRACE("MOVPIXS: onLeaveState\n");
+  MOVPIXS_TRACE("MOVPIXS: onLeaveState\n");
 
   ASSERT(m_pixelsMovement);
   ASSERT(editor == m_editor);
@@ -489,9 +491,23 @@ bool MovingPixelsState::onKeyUp(Editor* editor, KeyMessage* msg)
 
 bool MovingPixelsState::onUpdateStatusBar(Editor* editor)
 {
+  MOVPIXS_TRACE("MOVPIXS: onUpdateStatusBar (%p)\n", m_pixelsMovement.get());
+
   ASSERT(m_pixelsMovement);
   ASSERT(editor == m_editor);
 
+  // We've received a crash report where this is nullptr when
+  // MovingPixelsState::onLeaveState() generates a general update
+  // notification (notifyGeneralUpdate()) just after the
+  // m_pixelsMovement is deleted with removePixelsMovement(). The
+  // general update signals a scroll update in the view which will ask
+  // for the status bar content again (Editor::notifyScrollChanged).
+  //
+  // We weren't able to reproduce this scenario anyway (which should
+  // be visible with the ASSERT() above).
+  if (!m_pixelsMovement)
+    return false;
+
   const Transformation& transform(getTransformation(editor));
   gfx::Size imageSize = m_pixelsMovement->getInitialImageSize();
 
@@ -532,7 +548,7 @@ void MovingPixelsState::onBeforeCommandExecution(CommandExecutionEvent& ev)
 {
   Command* command = ev.command();
 
-  TRACE("MOVPIXS: onBeforeCommandExecution %s\n", command->id().c_str());
+  MOVPIXS_TRACE("MOVPIXS: onBeforeCommandExecution %s\n", command->id().c_str());
 
   // If the command is for other editor, we don't drop pixels.
   if (!isActiveEditor())
@@ -743,7 +759,7 @@ void MovingPixelsState::setTransparentColor(bool opaque, const app::Color& color
 
 void MovingPixelsState::dropPixels()
 {
-  TRACE("MOVPIXS: dropPixels\n");
+  MOVPIXS_TRACE("MOVPIXS: dropPixels\n");
 
   // Just change to default state (StandbyState generally). We'll
   // receive an onLeaveState() event after this call.
diff --git a/src/app/ui/file_selector.cpp b/src/app/ui/file_selector.cpp
index 1e8e2f6ca..3249bbce8 100644
--- a/src/app/ui/file_selector.cpp
+++ b/src/app/ui/file_selector.cpp
@@ -641,9 +641,10 @@ again:
     }
 #endif
 
-    // does it not have extension? ...we should add the extension
+    // Does it not have extension? ...we should add the extension
     // selected in the filetype combo-box
-    if (!buf.empty() && base::get_file_extension(buf).empty()) {
+    if (m_type == FileSelectorType::Save &&
+        !buf.empty() && base::get_file_extension(buf).empty()) {
       buf += '.';
       buf += getSelectedExtension();
     }
diff --git a/src/app/ui/preview_editor.cpp b/src/app/ui/preview_editor.cpp
index c86be5d86..b8111d126 100644
--- a/src/app/ui/preview_editor.cpp
+++ b/src/app/ui/preview_editor.cpp
@@ -483,10 +483,10 @@ void PreviewEditorWindow::destroyDocView()
 void PreviewEditorWindow::adjustPlayingTag()
 {
   Editor* editor = m_relatedEditor;
-  Editor* miniEditor = m_docView->editor();
+  if (!editor || !m_docView)
+    return;
 
-  ASSERT(editor);
-  ASSERT(miniEditor);
+  Editor* miniEditor = m_docView->editor();
 
   if (miniEditor->isPlaying()) {
     doc::Tag* tag = editor
diff --git a/src/app/util/open_batch.h b/src/app/util/open_batch.h
index 4b53e4581..39b43bc25 100644
--- a/src/app/util/open_batch.h
+++ b/src/app/util/open_batch.h
@@ -42,7 +42,10 @@ namespace app {
         }
       }
 
-      ctx->executeCommandFromMenuOrShortcut(&m_cmd, params);
+      if (ctx->isUIAvailable())
+        ctx->executeCommandFromMenuOrShortcut(&m_cmd, params);
+      else
+        ctx->executeCommand(&m_cmd, params);
 
       // Future decision for other files in the CLI
       auto d = m_cmd.seqDecision();
diff --git a/src/dio/aseprite_decoder.cpp b/src/dio/aseprite_decoder.cpp
index d8b3b8c34..be2ab6bfb 100644
--- a/src/dio/aseprite_decoder.cpp
+++ b/src/dio/aseprite_decoder.cpp
@@ -39,6 +39,22 @@ bool AsepriteDecoder::decode()
     return false;
   }
 
+  if (header.depth != 32 &&
+      header.depth != 16 &&
+      header.depth != 8) {
+    delegate()->error(
+      fmt::format("Invalid color depth {0}",
+                  header.depth));
+    return false;
+  }
+
+  if (header.width < 1 || header.height < 1) {
+    delegate()->error(
+      fmt::format("Invalid sprite size {0}x{1}",
+                  header.width, header.height));
+    return false;
+  }
+
   // Create the new sprite
   std::unique_ptr<doc::Sprite> sprite(
     new doc::Sprite(doc::ImageSpec(header.depth == 32 ? doc::ColorMode::RGB:
diff --git a/src/doc/algorithm/polygon.cpp b/src/doc/algorithm/polygon.cpp
index 4c23ec408..33f90041b 100644
--- a/src/doc/algorithm/polygon.cpp
+++ b/src/doc/algorithm/polygon.cpp
@@ -1,5 +1,5 @@
 // Aseprite Document Library
-// Copyright (c) 2019 Igara Studio S.A.
+// Copyright (c) 2019-2020 Igara Studio S.A.
 // Copyright (c) 2001-2014 David Capello
 //
 // This file is released under the terms of the MIT license.
@@ -9,6 +9,7 @@
 #include "config.h"
 #endif
 
+#include "base/debug.h"
 #include "doc/algo.h"
 #include "doc/algorithm/polygon.h"
 
diff --git a/src/ui/manager.cpp b/src/ui/manager.cpp
index 8caa9d0f6..b26c54c12 100644
--- a/src/ui/manager.cpp
+++ b/src/ui/manager.cpp
@@ -518,30 +518,7 @@ void Manager::handleMouseMove(const gfx::Point& mousePos,
                               const PointerType pointerType,
                               const float pressure)
 {
-  // Get the list of widgets to send mouse messages.
-  mouse_widgets_list.clear();
-  broadcastMouseMessage(mouse_widgets_list);
-
-  // Get the widget under the mouse
-  Widget* widget = nullptr;
-  for (auto mouseWidget : mouse_widgets_list) {
-    widget = mouseWidget->pick(mousePos);
-    if (widget) {
-      // Get the first ancestor of the picked widget that doesn't
-      // ignore mouse events.
-      while (widget && widget->hasFlags(IGNORE_MOUSE))
-        widget = widget->parent();
-      break;
-    }
-  }
-
-  // Fixup "mouse" flag
-  if (widget != mouse_widget) {
-    if (!widget)
-      freeMouse();
-    else
-      setMouse(widget);
-  }
+  updateMouseWidgets(mousePos);
 
   // Send the mouse movement message
   Widget* dst = (capture_widget ? capture_widget: mouse_widget);
@@ -683,6 +660,34 @@ void Manager::handleWindowZOrder()
   setFocus(mouse_widget);
 }
 
+void Manager::updateMouseWidgets(const gfx::Point& mousePos)
+{
+  // Get the list of widgets to send mouse messages.
+  mouse_widgets_list.clear();
+  broadcastMouseMessage(mouse_widgets_list);
+
+  // Get the widget under the mouse
+  Widget* widget = nullptr;
+  for (auto mouseWidget : mouse_widgets_list) {
+    widget = mouseWidget->pick(mousePos);
+    if (widget) {
+      // Get the first ancestor of the picked widget that doesn't
+      // ignore mouse events.
+      while (widget && widget->hasFlags(IGNORE_MOUSE))
+        widget = widget->parent();
+      break;
+    }
+  }
+
+  // Fixup "mouse" flag
+  if (widget != mouse_widget) {
+    if (!widget)
+      freeMouse();
+    else
+      setMouse(widget);
+  }
+}
+
 void Manager::dispatchMessages()
 {
   // Send messages in the queue (mouse/key/timer/etc. events) This
@@ -1103,9 +1108,7 @@ void Manager::_openWindow(Window* window)
 
   // Update mouse widget (as it can be a widget below the
   // recently opened window).
-  Widget* widget = pick(ui::get_mouse_position());
-  if (widget)
-    setMouse(widget);
+  updateMouseWidgets(ui::get_mouse_position());
 }
 
 void Manager::_closeWindow(Window* window, bool redraw_background)
@@ -1160,9 +1163,7 @@ void Manager::_closeWindow(Window* window, bool redraw_background)
 
   // Update mouse widget (as it can be a widget below the
   // recently closed window).
-  Widget* widget = pick(ui::get_mouse_position());
-  if (widget)
-    setMouse(widget);
+  updateMouseWidgets(ui::get_mouse_position());
 
   redrawState = RedrawState::AWindowHasJustBeenClosed;
 }
diff --git a/src/ui/manager.h b/src/ui/manager.h
index 1da5b6d86..4554548ad 100644
--- a/src/ui/manager.h
+++ b/src/ui/manager.h
@@ -145,6 +145,7 @@ namespace ui {
                             const KeyModifiers modifiers,
                             const double magnification);
     void handleWindowZOrder();
+    void updateMouseWidgets(const gfx::Point& mousePos);
 
     int pumpQueue();
     bool sendMessageToWidget(Message* msg, Widget* widget);