ref #64754

SelectBox: constructor, interface refactor.  Addresses: #58922

Add a space after theme/icon theme filters

fixes #63145

These methods return an IEditor as a result but even if the opening fails or the editor was not opened as active.

The fix is to check for the result of the open call and only return the editor if the editor was opened actually.

This restores the behaviour we had before GRID.

fixes #64767

fixes #64735

This reverts commit 7d76da21.

fixes #64233