MATE Terminal menu is not shown even if user have checked "Enable the menu shortcut key (F10 by default)" checkbox

[Norbert]

Steps to reproduce:
1. Have Ubuntu MATE 16.04 LTS installed
2. Open MATE Terminal
3. Select Edit - Keyboard Shortcuts, check "Enable the menu shortcut key (F10 by default)" checkbox, click Close
4. Press F10

Expected results:

* after pressing F10 the File menu is opened, rolled down and active

Actual results:

* after pressing F10 terminal shows the tilde symbol ("~"), the File menu is not opened

Notes:

1. The correct behavior was last seen on Ubuntu MATE 14.04 LTS (with MATE Terminal 1.8.1)
2. All newer supported versions are affected by this bug

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: mate-terminal 1.12.1-1
ProcVersionSignature: Ubuntu 4.15.0-46.49~16.04.1-generic 4.15.18
Uname: Linux 4.15.0-46-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.18
Architecture: amd64
CurrentDesktop: MATE
Date: Sun Apr 5 20:36:05 2020
InstallationDate: Installed on 2018-08-07 (607 days ago)
InstallationMedia: Ubuntu-MATE 16.04.3 LTS "Xenial Xerus" - Release amd64 (20170801)
SourcePackage: mate-terminal
UpgradeStatus: No upgrade log present (probably fresh install)

[Norbert (nrbrtx)]

Bug still exists in latest Ubuntu MATE 22.04 LTS.