GtkTextView: Long text with wrap forces window width
This is with gtk3-3.24.30. Get this test program, the first line says how to compile & run it.
When I change the window height, also the window width is modified, up until no text wraps. After that I cannot make the window smaller (horizontally).
I noticed that in the Evolution-data-server's alarm notify, it changes the window width also on Alt+Tab out-and-back, but I cannot reproduce this Alt+Tab with the test program. The window height change exhibits the problem, thus I believe it's in gtk+.