You can refer to this Bugzilla ticket which causes the changes you mentioned:phkhgh wrote:Hello yuoo2k,
As mentioned, the "Cancel" button is now missing from ABH2's UI, in Fx 47.0 final (Windows).
I'm using ABH 41.0.20160423 (automatically updated).
Really, if you hit Esc WHILE ABH pop up window is active window, ABH probably shouldn't just stick the bookmark in the "Bookmarks Menu" folder.
When it still had a cancel button, that was still the behavior if hit Esc instead of Cancel. Generally, if you escape out of a menu / screen, you don't want changes saved.
Is there any reason why that would be (is) different in ABH?
Are you using a firefox api for the add bookmark popup menu & tweaking it? Did they remove cancel button, or did you?
It's not the end of world, but cleaning the Bookmarks Menu folder is one more thing to do.
Thanks.
https://bugzilla.mozilla.org/show_bug.cgi?id=1219794