Use more native way to copy history while cloning tab, references #540
Simplify
Fix spacing typo
Add a 'Hide' button to the exit warning dialog
Allow to reload while tab dialogs are visible
Merge pull request #554 from beastie1/master

Add a 'Hide' button to the exit warning dialog
Constify
Allow to warn about quitting when using action from tray icon
Filter out meaningless warning, fixes #555