Fix Export to clipboard Dialog icon (#6345)

* Fix Export to clipboard Dialog icon

* Add entry to CHANGELOG.md

Co-authored-by: Christoph <siedlerkiller@gmail.com>

CHANGELOG.md

@@ -89,8 +89,10 @@ Note that this project **does not** adhere to [Semantic Versioning](http://semve
 - We fixed an issue where citation styles except the default "Preview" could not be used. [#56220](https://github.com/JabRef/jabref/issues/5622)
 - We fixed an issue where a warning was displayed when the title content is made up of two sentences. [#5832](https://github.com/JabRef/jabref/issues/5832)
 - We fixed an issue where an exception was thrown when adding a save action without a selected formatter in the library properties [#6069](https://github.com/JabRef/jabref/issues/6069)
+- We fixed an issue where JabRef's icon was missing in the Export to clipboard Dialog. [#6286](https://github.com/JabRef/jabref/issues/6286)
 - We fixed an issue when an "Abstract field" was duplicating text, when importing from RIS file (Neurons) [#6065](https://github.com/JabRef/jabref/issues/6065)
 
+
 ### Removed
 
 - Ampersands are no longer escaped by default in the `bib` file. If you want to keep the current behaviour, you can use the new "Escape Ampersands" formatter as a save action. [#5869](https://github.com/JabRef/jabref/issues/5869)

src/main/java/org/jabref/gui/JabRefDialogService.java

@@ -120,6 +120,7 @@ public static String shortenDialogMessage(String dialogMessage) {
     @Override
     public <T> Optional<T> showChoiceDialogAndWait(String title, String content, String okButtonLabel, T defaultChoice, Collection<T> choices) {
         ChoiceDialog<T> choiceDialog = new ChoiceDialog<>(defaultChoice, choices);
+        ((Stage) choiceDialog.getDialogPane().getScene().getWindow()).getIcons().add(IconTheme.getJabRefImageFX());
         ButtonType okButtonType = new ButtonType(okButtonLabel, ButtonBar.ButtonData.OK_DONE);
         choiceDialog.getDialogPane().getButtonTypes().setAll(ButtonType.CANCEL, okButtonType);
         choiceDialog.setHeaderText(title);