fix(ui): constrain tabs and preserve focus errors

- Prevent long editor and preview titles from monopolizing the tab bar while
  keeping their full text available through tooltips.
- Preserve the SetFocus result and error code before asynchronous activation
  messages can overwrite diagnostic state.

Author: nullmastermind

src/DockedEditor.cpp

@@ -29,10 +29,30 @@
 #include "ScintillaNext.h"
 
 #include <QEvent>
+#include <QFontMetrics>
 #include <QTimer>
 #include <QUuid>
 
 
+namespace {
+
+// Upper bound for a center tab's width. File and preview tabs (browser, embed,
+// file preview) can carry long titles; left uncapped a single tab expands to
+// its full text and monopolises the tab bar. Derived from the tab's own font so
+// it scales with the UI font / DPI rather than a hard-coded pixel value: ~28
+// average glyph widths plus fixed slack for the icon, close button and layout
+// margins. Cheap — one QFontMetrics query per tab creation, never on a hot path.
+int centerTabMaxWidth(const QWidget *tab)
+{
+    const QFontMetrics fm(tab->font());
+    constexpr int kTitleChars = 28;
+    constexpr int kChromeSlack = 56; // icon + close button + margins
+    return fm.averageCharWidth() * kTitleChars + kChromeSlack;
+}
+
+} // namespace
+
+
 class DockedEditorComponentsFactory : public ads::CDockComponentsFactory
 {
 public:
@@ -260,8 +280,10 @@ void DockedEditor::addEditor(ScintillaNext *editor)
     // Create the dock widget for the editor
     ads::CDockWidget *dockWidget = dockManager->createDockWidget(editor->getName());
 
-    // Disable elide, elided file names not readable when lots of files opened
-    dockWidget->tabWidget()->setElideMode(Qt::ElideNone);
+    // Keep long file names readable via the tooltip without letting one tab
+    // consume the entire tab bar.
+    dockWidget->tabWidget()->setElideMode(Qt::ElideRight);
+    dockWidget->tabWidget()->setMaximumWidth(centerTabMaxWidth(dockWidget->tabWidget()));
 
     // We need a unique object name. Can't use the name or file path so use a uuid
     dockWidget->setObjectName(QUuid::createUuid().toString());
@@ -400,9 +422,17 @@ ads::CDockWidget *DockedEditor::addPreviewTab(QWidget *widget, const QString &ti
     dockWidget->setFeature(ads::CDockWidget::DockWidgetFeature::DockWidgetDeleteOnClose, true);
     dockWidget->setFeature(ads::CDockWidget::DockWidgetFeature::DockWidgetFloatable, false);
 
-    dockWidget->tabWidget()->setElideMode(Qt::ElideNone);
+    // Preview tabs (browser/embed/file-preview) can carry long, dynamic titles
+    // such as web page <title>s. Cap the tab width and elide from the right so a
+    // single tab can't monopolise the tab bar; the full title stays reachable as
+    // a hover tooltip, kept in sync with subsequent dock-title changes.
+    auto *tab = dockWidget->tabWidget();
+    tab->setElideMode(Qt::ElideRight);
+    tab->setMaximumWidth(centerTabMaxWidth(tab));
+    tab->setToolTip(title);
+    connect(dockWidget, &QWidget::windowTitleChanged, tab, &QWidget::setToolTip);
     if (!icon.isNull())
-        dockWidget->tabWidget()->setIcon(icon);
+        tab->setIcon(icon);
 
     latestDockArea = dockManager->addDockWidget(ads::CenterDockWidgetArea, dockWidget, currentDockArea());
 

src/EmbeddedWindowWin32.cpp

@@ -326,23 +326,23 @@ bool focusForeign(quintptr targetHandle, quintptr token)
     // top-level window, so there is no separate top-level to SetActiveWindow.
     SetLastError(ERROR_SUCCESS);
     SetFocus(target);
+    const bool focused = GetFocus() == target;
+    const DWORD focusError = GetLastError();
     // Self-drawn apps (Godot, Chromium/Edge, ...) gate keyboard/IME input on
     // their OWN activation flag, which they update only from WM_NCACTIVATE /
     // WM_ACTIVATE. A WS_CHILD window never receives those (only top-levels do),
     // so after reparenting they believe they are inactive and silently drop
-    // every keystroke even though GetFocus() already points at them (proven by
-    // the diagnostic log: Godot/Edge keep GetActiveWindow on our Qt window).
+    // every keystroke even when Win32 focus already points at them.
     // Synthesize activation to re-enable their input path. PostMessage (async) so
     // a hung foreign message loop can never block our GUI thread — matches
     // syncGeometry. lParam (the "other" window) is left 0; these apps ignore it.
     if (!PostMessageW(target, WM_NCACTIVATE, TRUE, 0))
         qWarning("EmbeddedWindow: WM_NCACTIVATE post failed (err=%lu)", GetLastError());
     if (!PostMessageW(target, WM_ACTIVATE, MAKEWPARAM(WA_ACTIVE, 0), 0))
         qWarning("EmbeddedWindow: WM_ACTIVATE post failed (err=%lu)", GetLastError());
-    if (GetFocus() == target)
+    if (focused)
         return true;
-    const DWORD error = GetLastError();
-    qWarning("EmbeddedWindow: SetFocus on foreign child failed (err=%lu)", error);
+    qWarning("EmbeddedWindow: SetFocus on foreign child failed (err=%lu)", focusError);
     return false;
 #else
     Q_UNUSED(targetHandle) Q_UNUSED(token)