Sometimes Shutter can not select text in text fields

[Mingun]

Sometimes Shutter gets broken and do not process text selection events it text fields, for example:
- File rename dialog
- Text tool in screenshoot editor

When you press <Ctrl+A> (Select All), or trying to select text with mouse or using <hold Ctrl+left-right>, text is not selected. Only cursor moves. For me that only occurs after xneur switches the layout, but not after each switching, actually relatively rare (yes, I know that xneur is very bugged, but even after turning off xneur demon the problem doesn't disappear, so xneur can only be a trigger but not the cause of the problem).

Problem can be fixed only after restart Shutter

Version: Shutter 0.93.1, Rev.1278