Found as part of a downstream bug report by its reporter:
https://bugzilla.redhat.com/show_bug.cgi?id=651198

a) open composer
b) add an empty line, select it, deselect it
c) right-click with the mouse, see the Copy action is enabled, press it
d) right-click and choose Paste.

if the above was done in plain text mode then only a critical warning is
printed on the console:
> composer-CRITICAL **: e_composer_paste_text: assertion `text != NULL' failed

if in the HTML mode, then the evolution crashes with the below backtrace. The
only "issue" is that it is a different crash than the initial.

I committed workarounds to evo master (80d11c3 in 2.91.3+) and evo gnome-2-32 (29afee0 in 2.32.1+) till proper fix will be found. Basically, the EFocusTracker is checking actions' availability mainly based on the primary clipboard, but that's not correct, because it cannot know from where will the action ask its data, either selection clipboard or primary clipboard. For gtkhtml it asks itself, but there is nothing selected, so it returns nothing (NULL) later, which leads to critical warnings and/or the crash.

Cut&Copy should not be enabled when there is no selection in the widget it belongs to.

+ Trace 224592