add upstream 12.0

12 files changed, 149 insertions, 86 deletions

diff --git a/wx+/context_menu.h b/wx+/context_menu.h
index d1d2bd9f..92d8504c 100644
--- a/wx+/context_menu.h
+++ b/wx+/context_menu.h
@@ -126,6 +126,9 @@ void fixMenuIcons(wxMenu& menu)
 }
 
 
+//better call wxClipboard::Get()->Flush() *once* during app exit instead of after each setClipboardText()?
+//  => OleFlushClipboard: "Carries out the clipboard shutdown sequence"
+//  => maybe this helps with clipboard randomly "forgetting" content after app exit?
 inline
 void setClipboardText(const wxString& txt)
 {
@@ -133,9 +136,8 @@ void setClipboardText(const wxString& txt)
     if (clip.Open())
     {
         ZEN_ON_SCOPE_EXIT(clip.Close());
-        [[maybe_unused]] const bool rv1 = clip.SetData(new wxTextDataObject(txt)); //ownership passed
-        [[maybe_unused]] const bool rv2 = clip.Flush();
-        assert(rv1 && rv2);
+        [[maybe_unused]] const bool rv = clip.SetData(new wxTextDataObject(txt)); //ownership passed
+        assert(rv);
     }
     else assert(false);
 }
diff --git a/wx+/dc.h b/wx+/dc.h
index 48d0fe72..e0cb2c87 100644
--- a/wx+/dc.h
+++ b/wx+/dc.h
@@ -147,6 +147,14 @@ void setScaleFactor(wxDC& dc, double scale)
 }
 
 
+//add some sanity to moronic const/non-const wxRect::Intersect()
+inline
+wxRect getIntersection(const wxRect& rect1, const wxRect& rect2)
+{
+    return rect1.Intersect(rect2);
+}
+
+
 //---------------------- implementation ------------------------
 class RecursiveDcClipper
 {
@@ -158,8 +166,7 @@ public:
         {
             oldRect_ = it->second;
 
-            wxRect tmp = r;
-            tmp.Intersect(*oldRect_); //better safe than sorry
+            const wxRect tmp = getIntersection(r, *oldRect_); //better safe than sorry
 
             assert(!tmp.IsEmpty()); //"setting an empty clipping region is equivalent to DestroyClippingRegion()"
 
diff --git a/wx+/file_drop.cpp b/wx+/file_drop.cpp
index 86db57c1..cd233c56 100644
--- a/wx+/file_drop.cpp
+++ b/wx+/file_drop.cpp
@@ -60,8 +60,7 @@ private:
             filePaths.push_back(utfTo<Zstring>(file));
 
         //create a custom event on drop window: execute event after file dropping is completed! (after mouse is released)
-        if (wxEvtHandler* handler = dropWindow_.GetEventHandler())
-            handler->AddPendingEvent(FileDropEvent(filePaths));
+        dropWindow_.GetEventHandler()->AddPendingEvent(FileDropEvent(filePaths));
         return true;
     }
 
diff --git a/wx+/graph.cpp b/wx+/graph.cpp
index ce65d299..07268f34 100644
--- a/wx+/graph.cpp
+++ b/wx+/graph.cpp
@@ -247,7 +247,7 @@ void cutPoints(std::vector<CurvePoint>& curvePoints, std::vector<unsigned char>&
 
     auto savePoint = [&](const CurvePoint& pt, bool markedOob) { curvePointsTmp.push_back(pt); oobMarkerTmp.push_back(markedOob); };
 
-     bool pointInside = isInside(curvePoints[0]);
+    bool pointInside = isInside(curvePoints[0]);
     if (pointInside)
         savePoint(curvePoints[0], isMarkedOob(0));
 
@@ -283,7 +283,7 @@ void cutPoints(std::vector<CurvePoint>& curvePoints, std::vector<unsigned char>&
 struct GetIntersectionX
 {
     explicit GetIntersectionX(double x) : x_(x) {}
-    
+
     CurvePoint operator()(const CurvePoint& from, const CurvePoint& to) const
     {
         const double deltaX = to.x - from.x;
@@ -493,9 +493,7 @@ void Graph2D::onMouseLeftUp(wxMouseEvent& event)
     {
         if (activeSel_->getStartPos() != activeSel_->refCurrentPos()) //if it's just a single mouse click: discard selection
         {
-            GraphSelectEvent selEvent(activeSel_->refSelection()); //fire off GraphSelectEvent
-            if (wxEvtHandler* handler = GetEventHandler())
-                handler->AddPendingEvent(selEvent);
+            GetEventHandler()->AddPendingEvent(GraphSelectEvent(activeSel_->refSelection()));
 
             oldSel_.push_back(activeSel_->refSelection()); //commit selection
         }
diff --git a/wx+/grid.cpp b/wx+/grid.cpp
index 0ffee3a7..f997d72c 100644
--- a/wx+/grid.cpp
+++ b/wx+/grid.cpp
@@ -295,9 +295,7 @@ public:
     template <class T>
     bool sendEventToParent(T&& event) //take both "rvalue + lvalues", return "true" if a suitable event handler function was found and executed, and the function did not call wxEvent::Skip.
     {
-        if (wxEvtHandler* evtHandler = parent_.GetEventHandler())
-            return evtHandler->ProcessEvent(event);
-        return false;
+        return parent_.GetEventHandler()->ProcessEvent(event);
     }
 
 protected:
@@ -1412,8 +1410,7 @@ private:
         if (!gridUpdatePending_) //without guarding, the number of outstanding async events can become very high during scrolling!! test case: Ubuntu: 170; Windows: 20
         {
             gridUpdatePending_ = true;
-            wxCommandEvent scrollEvent(EVENT_GRID_HAS_SCROLLED);
-            AddPendingEvent(scrollEvent); //asynchronously call updateAfterScroll()
+            GetEventHandler()->AddPendingEvent(wxCommandEvent(EVENT_GRID_HAS_SCROLLED)); //asynchronously call updateAfterScroll()
         }
     }
 
@@ -1776,8 +1773,7 @@ void Grid::onKeyDown(wxKeyEvent& event)
             const wxPoint mousePos = mainWin_->GetPosition() + wxPoint(0, clientPosMainWinY); //mainWin_-relative to Grid-relative
 
             GridContextMenuEvent contextEvent(mousePos);
-            if (wxEvtHandler* evtHandler = GetEventHandler())
-                evtHandler->ProcessEvent(contextEvent);
+            GetEventHandler()->ProcessEvent(contextEvent);
         }
         return;
 
@@ -1907,19 +1903,21 @@ void Grid::selectRange(size_t rowFirst, size_t rowLast, bool positive, GridEvent
 void Grid::selectRange2(size_t rowFirst, size_t rowLast, bool positive, const GridClickEvent* mouseClick, GridEventPolicy rangeEventPolicy)
 {
     assert(rowFirst <= rowLast);
+    assert(getRowCount() == selection_.gridSize());
+    rowFirst = std::clamp<size_t>(rowFirst, 0, selection_.gridSize());
+    rowLast  = std::clamp<size_t>(rowLast,  0, selection_.gridSize());
 
-    const size_t rowCount = getRowCount();
-    rowFirst = std::clamp<size_t>(rowFirst, 0, rowCount);
-    rowLast  = std::clamp<size_t>(rowLast,  0, rowCount);
-
-    selection_.selectRange(rowFirst, rowLast, positive);
-    mainWin_->Refresh();
+    if (rowFirst < rowLast && !selection_.matchesRange(rowFirst, rowLast, positive))
+    {
+        selection_.selectRange(rowFirst, rowLast, positive);
+        mainWin_->Refresh();
+    }
 
+    //issue event even for unchanged selection! e.g. MainWin::onMouseDown() temporarily clears range with GridEventPolicy::deny!
     if (rangeEventPolicy == GridEventPolicy::allow)
     {
         GridSelectEvent selEvent(rowFirst, rowLast, positive, mouseClick);
-        if (wxEvtHandler* evtHandler = GetEventHandler())
-            [[maybe_unused]] const bool processed = evtHandler->ProcessEvent(selEvent);
+        [[maybe_unused]] const bool processed = GetEventHandler()->ProcessEvent(selEvent);
     }
 }
 
@@ -1962,8 +1960,19 @@ void Grid::Refresh(bool eraseBackground, const wxRect* rect)
         updateWindowSizes();
     }
 
-    if (selection_.gridSize() != rowCountNew) //clear selection only when needed (consider setSelectedRows())
-        selection_.init(rowCountNew);
+    if (selection_.gridSize() != rowCountNew)
+    {
+        const bool priorSelection = !selection_.matchesRange(0, selection_.gridSize(), false /*positive*/);
+
+        selection_.resize(rowCountNew);
+
+        if (priorSelection) //clear selection only when needed
+        {
+            //clearSelection(GridEventPolicy::allow); -> no, we need async event to make filegrid::refresh(*m_gridMainL, *m_gridMainC, *m_gridMainR) work
+            selection_.clear();
+            GetEventHandler()->AddPendingEvent(GridSelectEvent(0, rowCountNew, false /*positive*/, nullptr /*mouseClick*/));
+        }
+    }
 
     wxScrolledWindow::Refresh(eraseBackground, rect);
 }
@@ -2306,13 +2315,10 @@ void Grid::setColumnWidth(int width, size_t col, GridEventPolicy columnResizeEve
         if (columnResizeEventPolicy == GridEventPolicy::allow)
         {
             GridColumnResizeEvent sizeEvent(vcRs.offset, vcRs.type);
-            if (wxEvtHandler* evtHandler = GetEventHandler())
-            {
-                if (notifyAsync)
-                    evtHandler->AddPendingEvent(sizeEvent);
-                else
-                    evtHandler->ProcessEvent(sizeEvent);
-            }
+            if (notifyAsync)
+                GetEventHandler()->AddPendingEvent(sizeEvent);
+            else
+                GetEventHandler()->ProcessEvent(sizeEvent);
         }
     }
     else
diff --git a/wx+/grid.h b/wx+/grid.h
index 3b3e76b7..302abda8 100644
--- a/wx+/grid.h
+++ b/wx+/grid.h
@@ -97,9 +97,6 @@ struct GridContextMenuEvent : public wxEvent
 };
 //------------------------------------------------------------------------------------------------------------
 
-class Grid;
-
-
 class GridData
 {
 public:
@@ -113,21 +110,21 @@ public:
     virtual void         renderCell        (wxDC& dc, const wxRect& rect, size_t row, ColumnType colType, bool enabled, bool selected, HoverArea rowHover);
     virtual int          getBestSize       (wxDC& dc, size_t row, ColumnType colType); //must correspond to renderCell()!
     virtual HoverArea    getMouseHover     (wxDC& dc, size_t row, ColumnType colType, int cellRelativePosX, int cellWidth) { return HoverArea::none; }
-    virtual std::wstring getToolTip        (size_t row, ColumnType colType, HoverArea rowHover) { return std::wstring(); }
+    virtual std::wstring getToolTip        (          size_t row, ColumnType colType, HoverArea rowHover) { return std::wstring(); }
 
     //label area:
     virtual std::wstring getColumnLabel(ColumnType colType) const = 0;
     virtual void renderColumnLabel(wxDC& dc, const wxRect& rect, ColumnType colType, bool enabled, bool highlighted); //default implementation
     virtual std::wstring getToolTip(ColumnType colType) const { return std::wstring(); }
 
+    //optional helper routines:
     static int getColumnGapLeft(); //for left-aligned text
     static wxColor getColorSelectionGradientFrom();
     static wxColor getColorSelectionGradientTo();
 
-    //optional helper routines:
     static void drawCellText(wxDC& dc, const wxRect& rect, const std::wstring& text,
-                             int alignment = wxALIGN_LEFT | wxALIGN_CENTER_VERTICAL, const wxSize* textExtentHint = nullptr); //returns text extent
-    static wxRect drawCellBorder    (wxDC& dc, const wxRect& rect); //returns inner rectangle
+                             int alignment = wxALIGN_LEFT | wxALIGN_CENTER_VERTICAL, const wxSize* textExtentHint = nullptr);
+    static wxRect drawCellBorder(wxDC& dc, const wxRect& rect); //returns inner rectangle
 
     static wxRect drawColumnLabelBackground(wxDC& dc, const wxRect& rect, bool highlighted); //returns inner rectangle
     static void   drawColumnLabelText      (wxDC& dc, const wxRect& rect, const std::wstring& text, bool enabled);
@@ -253,7 +250,7 @@ private:
     class Selection
     {
     public:
-        void init(size_t rowCount) { selected_.resize(rowCount); clear(); }
+        void resize(size_t rowCount) { selected_.resize(rowCount, false); }
 
         size_t gridSize() const { return selected_.size(); }
 
@@ -266,20 +263,30 @@ private:
             return result;
         }
 
-        void clear() { selectRange(0, selected_.size(), false); }
-
         bool isSelected(size_t row) const { return row < selected_.size() ? selected_[row] != 0 : false; }
 
-        void selectRange(size_t rowFirst, size_t rowLast, bool positive = true) //select [rowFirst, rowLast), trims if required!
+        bool matchesRange(size_t rowFirst, size_t rowLast, bool positive)
         {
-            if (rowFirst <= rowLast)
+            if (rowFirst <= rowLast && rowLast <= selected_.size())
             {
-                rowFirst = std::clamp<size_t>(rowFirst, 0, selected_.size());
-                rowLast  = std::clamp<size_t>(rowLast,  0, selected_.size());
-
-                std::fill(selected_.begin() + rowFirst, selected_.begin() + rowLast, positive);
+                const auto rangeEnd = selected_.begin() + rowLast;
+                return std::find(selected_.begin() + rowFirst, rangeEnd, static_cast<unsigned char>(!positive)) == rangeEnd;
             }
-            else assert(false);
+            else
+            {
+                assert(false);
+                return false;
+            }
+        }
+
+        void clear() { selectRange(0, selected_.size(), false); }
+
+        void selectRange(size_t rowFirst, size_t rowLast, bool positive = true) //select [rowFirst, rowLast), trims if required!
+        {
+            assert(rowFirst <= rowLast && rowLast <= selected_.size());
+            if (rowFirst < rowLast)
+                std::fill(selected_.begin() + std::min(rowFirst, selected_.size()),
+                          selected_.begin() + std::min(rowLast,  selected_.size()), positive);
         }
 
     private:
diff --git a/wx+/image_resources.cpp b/wx+/image_resources.cpp
index 667b5912..823e867e 100644
--- a/wx+/image_resources.cpp
+++ b/wx+/image_resources.cpp
@@ -70,7 +70,7 @@ ImageHolder xbrzScale(int width, int height, const unsigned char* imageRgb, cons
 }
 
 
-auto createScalerTask(const std::string& imageName, const wxImage& img, int hqScale, Protected<std::vector<std::pair<std::string, ImageHolder>>>& result)
+auto createScalerTask(const std::string& imageName, const wxImage& img, int hqScale, Protected<std::vector<std::pair<std::string, ImageHolder>>>& protResult)
 {
     assert(runningOnMainThread());
     return [imageName,
@@ -78,10 +78,10 @@ auto createScalerTask(const std::string& imageName, const wxImage& img, int hqSc
             height = img.GetHeight(), //don't call wxWidgets functions from worker thread
             rgb    = img.GetData(),   //
             alpha  = img.GetAlpha(),  //
-            hqScale, &result]
+            hqScale, &protResult]
     {
         ImageHolder ih = xbrzScale(width, height, rgb, alpha, hqScale);
-        result.access([&](std::vector<std::pair<std::string, ImageHolder>>& r) { r.emplace_back(imageName, std::move(ih)); });
+        protResult.access([&](std::vector<std::pair<std::string, ImageHolder>>& result) { result.emplace_back(imageName, std::move(ih)); });
     };
 }
 
@@ -97,7 +97,7 @@ public:
     {
         assert(runningOnMainThread());
         imgKeeper_.push_back(img); //retain (ref-counted) wxImage so that the rgb/alpha pointers remain valid after passed to threads
-        threadGroup_->run(createScalerTask(imageName, img, hqScale_, result_));
+        threadGroup_->run(createScalerTask(imageName, img, hqScale_, protResult_));
     }
 
     std::unordered_map<std::string, wxImage> waitAndGetResult()
@@ -107,9 +107,9 @@ public:
 
         std::unordered_map<std::string, wxImage> output;
 
-        result_.access([&](std::vector<std::pair<std::string, ImageHolder>>& r)
+        protResult_.access([&](std::vector<std::pair<std::string, ImageHolder>>& result)
         {
-            for (auto& [imageName, ih] : r)
+            for (auto& [imageName, ih] : result)
             {
                 wxImage img(ih.getWidth(), ih.getHeight(), ih.releaseRgb(), false /*static_data*/); //pass ownership
                 img.SetAlpha(ih.releaseAlpha(), false /*static_data*/);
@@ -123,7 +123,7 @@ public:
 private:
     const int hqScale_;
     std::vector<wxImage> imgKeeper_;
-    Protected<std::vector<std::pair<std::string, ImageHolder>>> result_;
+    Protected<std::vector<std::pair<std::string, ImageHolder>>> protResult_;
 
     using TaskType = FunctionReturnTypeT<decltype(&createScalerTask)>;
     std::optional<ThreadGroup<TaskType>> threadGroup_{ThreadGroup<TaskType>(std::max<int>(std::thread::hardware_concurrency(), 1), Zstr("xBRZ Scaler"))};
@@ -195,7 +195,7 @@ ImageBuffer::ImageBuffer(const Zstring& zipPath) //throw FileError
     catch (FileError&) //fall back to folder: dev build (only!?)
     {
         const Zstring fallbackFolder = beforeLast(zipPath, Zstr(".zip"), IfNotFoundReturn::none);
-        if (!itemStillExists(fallbackFolder)) //throw FileError
+        if (!itemExists(fallbackFolder)) //throw FileError
             throw;
 
         traverseFolder(fallbackFolder, [&](const FileInfo& fi)
@@ -205,7 +205,7 @@ ImageBuffer::ImageBuffer(const Zstring& zipPath) //throw FileError
                 std::string stream = getFileContent(fi.fullPath, nullptr /*notifyUnbufferedIO*/); //throw FileError
                 streams.emplace_back(fi.itemName, std::move(stream));
             }
-        }, nullptr, nullptr, [](const std::wstring& errorMsg) { throw FileError(errorMsg); });
+        }, nullptr, nullptr); //throw FileError
     }
     //--------------------------------------------------------------------
 
diff --git a/wx+/no_flicker.h b/wx+/no_flicker.h
index 185ee052..1c91bd48 100644
--- a/wx+/no_flicker.h
+++ b/wx+/no_flicker.h
@@ -123,7 +123,7 @@ void setTextWithUrls(wxRichTextCtrl& richCtrl, const wxString& newText)
     using KeyEventsFun = void(*)(wxKeyEvent& event);
     static const KeyEventsFun onKeyEvents = [](wxKeyEvent& event)
     {
-        wxRichTextCtrl& richCtrl = dynamic_cast<UserData*>(event.GetEventUserData())->richCtrl; //unclear if we can rely on event.GetEventObject() == richCtrl
+        wxRichTextCtrl& richCtrl2 = dynamic_cast<UserData*>(event.GetEventUserData())->richCtrl; //unclear if we can rely on event.GetEventObject() == richCtrl
 
         //CTRL/SHIFT + INS is broken for wxRichTextCtrl on Windows/Linux (apparently never was a thing on macOS)
         if (event.ControlDown())
@@ -131,8 +131,8 @@ void setTextWithUrls(wxRichTextCtrl& richCtrl, const wxString& newText)
             {
                 case WXK_INSERT:
                 case WXK_NUMPAD_INSERT:
-                    assert(richCtrl.CanCopy()); //except when no selection
-                    richCtrl.Copy();
+                    assert(richCtrl2.CanCopy()); //except when no selection
+                    richCtrl2.Copy();
                     return;
             }
 
@@ -141,8 +141,8 @@ void setTextWithUrls(wxRichTextCtrl& richCtrl, const wxString& newText)
             {
                 case WXK_INSERT:
                 case WXK_NUMPAD_INSERT:
-                    assert(richCtrl.CanPaste()); //except wxTE_READONLY
-                    richCtrl.Paste();
+                    assert(richCtrl2.CanPaste()); //except wxTE_READONLY
+                    richCtrl2.Paste();
                     return;
             }
         event.Skip();
diff --git a/wx+/popup_dlg.cpp b/wx+/popup_dlg.cpp
index dfa5494f..c30426cb 100644
--- a/wx+/popup_dlg.cpp
+++ b/wx+/popup_dlg.cpp
@@ -150,15 +150,9 @@ public:
         if (iconTmp.IsOk())
             setImage(*m_bitmapMsgType, iconTmp);
 
-        if (titleTmp.empty())
-            SetTitle(wxTheApp->GetAppDisplayName());
-        else
-        {
-            if (parent && parent->IsShownOnScreen())
-                SetTitle(titleTmp);
-            else
-                SetTitle(wxTheApp->GetAppDisplayName() + SPACED_DASH + titleTmp);
-        }
+        if (!parent || !parent->IsShownOnScreen())
+            titleTmp = wxTheApp->GetAppDisplayName() + (!titleTmp.empty() ? SPACED_DASH + titleTmp : wxString());
+        SetTitle(titleTmp);
 
         int maxWidth  = fastFromDIP(500);
         int maxHeight = fastFromDIP(400); //try to determine better value based on actual display resolution:
diff --git a/wx+/popup_dlg_generated.cpp b/wx+/popup_dlg_generated.cpp
index fb449d13..b7e3d94d 100644
--- a/wx+/popup_dlg_generated.cpp
+++ b/wx+/popup_dlg_generated.cpp
@@ -98,3 +98,27 @@ PopupDialogGenerated::PopupDialogGenerated( wxWindow* parent, wxWindowID id, con
 PopupDialogGenerated::~PopupDialogGenerated()
 {
 }
+
+TooltipDlgGenerated::TooltipDlgGenerated( wxWindow* parent, wxWindowID id, const wxString& title, const wxPoint& pos, const wxSize& size, long style ) : wxDialog( parent, id, title, pos, size, style )
+{
+    this->SetSizeHints( wxDefaultSize, wxDefaultSize );
+
+    wxBoxSizer* bSizer158;
+    bSizer158 = new wxBoxSizer( wxHORIZONTAL );
+
+    m_bitmapLeft = new wxStaticBitmap( this, wxID_ANY, wxNullBitmap, wxDefaultPosition, wxDefaultSize, 0 );
+    bSizer158->Add( m_bitmapLeft, 0, wxALL|wxALIGN_CENTER_VERTICAL, 5 );
+
+    m_staticTextMain = new wxStaticText( this, wxID_ANY, _("dummy"), wxDefaultPosition, wxDefaultSize, 0 );
+    m_staticTextMain->Wrap( 600 );
+    bSizer158->Add( m_staticTextMain, 0, wxALL|wxALIGN_CENTER_HORIZONTAL|wxALIGN_CENTER_VERTICAL, 5 );
+
+
+    this->SetSizer( bSizer158 );
+    this->Layout();
+    bSizer158->Fit( this );
+}
+
+TooltipDlgGenerated::~TooltipDlgGenerated()
+{
+}
diff --git a/wx+/popup_dlg_generated.h b/wx+/popup_dlg_generated.h
index 6218c6d8..ce4e2ac8 100644
--- a/wx+/popup_dlg_generated.h
+++ b/wx+/popup_dlg_generated.h
@@ -70,3 +70,22 @@ public:
 
 };
 
+///////////////////////////////////////////////////////////////////////////////
+/// Class TooltipDlgGenerated
+///////////////////////////////////////////////////////////////////////////////
+class TooltipDlgGenerated : public wxDialog
+{
+private:
+
+protected:
+
+public:
+    wxStaticBitmap* m_bitmapLeft;
+    wxStaticText* m_staticTextMain;
+
+    TooltipDlgGenerated( wxWindow* parent, wxWindowID id = wxID_ANY, const wxString& title = wxEmptyString, const wxPoint& pos = wxDefaultPosition, const wxSize& size = wxDefaultSize, long style = wxDEFAULT_DIALOG_STYLE );
+
+    ~TooltipDlgGenerated();
+
+};
+
diff --git a/wx+/tooltip.cpp b/wx+/tooltip.cpp
index a3fa770d..c56d80a1 100644
--- a/wx+/tooltip.cpp
+++ b/wx+/tooltip.cpp
@@ -27,10 +27,9 @@ const int TIP_WINDOW_OFFSET_DIP = 30;
 class Tooltip::TooltipDlgGenerated : public wxDialog
 {
 public:
-    TooltipDlgGenerated(wxWindow* parent) : wxDialog(parent, wxID_ANY, L"" /*title*/, wxDefaultPosition, wxDefaultSize, 0 /*style*/)
+    TooltipDlgGenerated(wxWindow* parent) : //Suse Linux/X11: needs parent window, else there are z-order issues
+        wxDialog(parent, wxID_ANY, L"" /*title*/, wxDefaultPosition, wxDefaultSize, 0 /*style*/)
     {
-        //Suse Linux/X11: needs parent window, else there are z-order issues
-
         SetSizeHints(wxDefaultSize, wxDefaultSize);
         SetExtraStyle(this->GetExtraStyle() | wxWS_EX_TRANSIENT);
         SetBackgroundColour(wxSystemSettings::GetColour(wxSYS_COLOUR_INFOBK));   //both required: on Ubuntu background is black, foreground white!
@@ -44,11 +43,11 @@ public:
         bSizer158->Add(staticTextMain_, 0, wxALL | wxALIGN_CENTER_HORIZONTAL | wxALIGN_CENTER_VERTICAL, 5);
 
         SetSizer(bSizer158);
-        Layout();
-        bSizer158->Fit(this);
 
     }
 
+    bool AcceptsFocus() const override { return false; } //any benefit?
+
     wxStaticText* staticTextMain_ = nullptr;
     wxStaticBitmap* bitmapLeft_   = nullptr;
 };
@@ -61,21 +60,28 @@ void Tooltip::show(const wxString& text, wxPoint mousePos, const wxImage* img)
 
     const wxImage& newImg = img ? *img : wxNullImage;
 
-    if (!lastUsedImg_.IsSameAs(newImg))
+    const bool imgChanged = !newImg.IsSameAs(lastUsedImg_);
+    const bool txtChanged = text != tipWindow_->staticTextMain_->GetLabelText();
+
+    if (imgChanged)
     {
         lastUsedImg_ = newImg;
         setImage(*tipWindow_->bitmapLeft_, newImg);
-        tipWindow_->Refresh(); //needed if bitmap size changed!
+        // tipWindow_->Refresh(); //needed if bitmap size changed!    ->???
     }
 
-    if (text != tipWindow_->staticTextMain_->GetLabelText())
+    if (txtChanged)
     {
         tipWindow_->staticTextMain_->SetLabelText(text);
         tipWindow_->staticTextMain_->Wrap(fastFromDIP(600));
     }
 
-    tipWindow_->GetSizer()->SetSizeHints(tipWindow_); //~=Fit() + SetMinSize()
-    //Linux: Fit() seems to be broken => this needs to be called EVERY time inside show, not only if text or bmp change
+    if (imgChanged || txtChanged)
+    {
+        //tipWindow_->Layout(); -> apparently not needed!?
+        tipWindow_->GetSizer()->SetSizeHints(tipWindow_); //~=Fit() + SetMinSize()
+        //Linux: Fit() seems to be broken => call EVERY time inside show, not only if text or bmp change -> still true?!?
+    }
 
     const wxPoint newPos = wxTheApp->GetLayoutDirection() == wxLayout_RightToLeft ?
                            mousePos - wxPoint(fastFromDIP(TIP_WINDOW_OFFSET_DIP) + tipWindow_->GetSize().GetWidth(), 0) :
@@ -98,6 +104,7 @@ void Tooltip::hide()
 #if GTK_MAJOR_VERSION == 2 //the tooltip sometimes turns blank or is not shown again after it was hidden: e.g. drag-selection on middle grid
         tipWindow_->Destroy(); //apply brute force:
         tipWindow_ = nullptr;  //
+        lastUsedImg_ = wxNullImage;
 
 #elif GTK_MAJOR_VERSION == 3
         tipWindow_->Hide();