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bundles/org.eclipse.ui.workbench.texteditor/src/org/eclipse/ui/internal/findandreplace/overlay/FindReplaceOverlay.java

@@ -143,10 +143,25 @@ private final class KeyboardShortcuts {
 	private Color normalTextForegroundColor;
 	private boolean positionAtTop = true;
 	private boolean isTargetVisible = true;
+	private final Runnable onParentShellChange;
 
-	public FindReplaceOverlay(Shell parent, IWorkbenchPart part, IFindReplaceTarget target) {
+	/**
+	 * Constructs the Overlay.
+	 *
+	 * @param parent              the parent shell
+	 * @param part                the {@code ViewPart} which is targeted by the
+	 *                            overlay
+	 * @param target              the {@code FindReplaceTarget} used as target for
+	 *                            performing the find/replace operations
+	 * @param onParentShellChange if the targeted ViewPart is moved to another
+	 *                            shell, the overlay closes itself and calls this
+	 *                            callback to notify the client.
+	 */
+	public FindReplaceOverlay(Shell parent, IWorkbenchPart part, IFindReplaceTarget target,
+			Runnable onParentShellChange) {
 		super(parent);
 		createFindReplaceLogic(target);
+		this.onParentShellChange = onParentShellChange;
 
 		setShellStyle(SWT.MODELESS);
 		setBlockOnOpen(false);
@@ -841,6 +856,7 @@ private void repositionTextSelection() {
 
 	private void updatePlacementAndVisibility() {
 		if (isInvalidTargetShell()) {
+			getShell().getDisplay().asyncExec(onParentShellChange);
 			close();
 			return;
 		}

bundles/org.eclipse.ui.workbench.texteditor/src/org/eclipse/ui/texteditor/FindReplaceAction.java

@@ -420,7 +420,11 @@ private void showOverlayInEditor() {
 			} else {
 				shellToUse = fShell;
 			}
-			overlay = new FindReplaceOverlay(shellToUse, fWorkbenchPart, fTarget);
+			overlay = new FindReplaceOverlay(shellToUse, fWorkbenchPart, fTarget, () -> {
+				overlay = null;
+				showOverlayInEditor();
+				fWorkbenchPart.setFocus();
+			});
 			hookDialogPreferenceListener();
 
 			FindReplaceOverlayFirstTimePopup.displayPopupIfNotAlreadyShown(shellToUse);