Re: Closing displays GTK+ bug

[Ulrich Mueller]

>>>>> On Fri, 17 Apr 2020, Richard Stallman wrote:

> Qt has a fatal flaw (from our point of view) -- it is released only
> under GPL versions 2 and 3.  If we ever need to make a GPL version 4,
> we will want to advance Emacs to GPL 4-or-later.  If we depended on Qt,
> we would be blocked from upgrading the license version.  We must not
> get into that difficulty.  

> So we must avoid using Qt.

IIUC, only a few add-on components of Qt are licensed under the GPL.
Its core libraries are licensed under the LGPL, version 3.