Deprecation warning on startup

[kneekoo]

Describe the bug
A few deprecation notices, just something for the to do list.

Terminal output

nicu@nas:~$ mintupdate
nicu@nas:~$ /usr/lib/linuxmint/mintUpdate/mintUpdate.py:1274: DeprecationWarning: Gdk.threads_init is deprecated
  Gdk.threads_init()
/usr/lib/linuxmint/mintUpdate/mintUpdate.py:1422: DeprecationWarning: Gtk.ImageMenuItem.set_image is deprecated
  menuItem3.set_image(image)
/usr/lib/linuxmint/mintUpdate/mintUpdate.py:722: DeprecationWarning: Gdk.threads_enter is deprecated
  Gdk.threads_enter()
/usr/lib/linuxmint/mintUpdate/mintUpdate.py:729: DeprecationWarning: Gdk.threads_leave is deprecated
  Gdk.threads_leave()

To Reproduce
Start mintUpdate from the terminal.

Expected behavior
No warnings.

Distribution: Linux Mint 20.2

Software version:
mintUpdate 5.7.8

[xenopeek]

These warnings may become relevant with Linux Mint 21 development cycle, when moving to a newer package base that may have a newer Gdk version. They are not bugs; the program is not doing something differently from what it is designed to do.

[kneekoo]

gdk_threads_init(), gdk-threads-enter(), gdk_threads_leave():

gdk_threads_init/gdk_threads_enter/gdk_threads_leave has been deprecated since version 3.6 and should not be used in newly-written code.
All GDK and GTK+ calls should be made from the main thread

What's really weird is that the stable Gtk documentation doesn't mention the deprecation of Gtk.ImageMenuItem.set_image. The only place I found mentioning this is the Vala documentation:

Warning: ImageMenuItem is deprecated since 3.10.

So it will matter in the future, but the they don't say when they'll remove these. Maybe that's because they plan keeping them for longer.

[timur-g]

Still in Mint 21.3.