Menu item with mnemonic gets cut off

[le_becc]

I'm not sure whether this is specific to Qt6, but that's what I'm on. When my longest menu item has a mnemonic, it gets shortened while the same item without mnemonics gets displayed fully:

Once there's another item in the menu that's longer, everything is fine.

I'm on Debian Linux+Gnome+XOrg. Tthis is my example in PyQt:

import sys
from PyQt6 import QtGui, QtWidgets
from PyQt6.QtCore import Qt

TXT = '&Show Scrollbars'
TXT_PLAIN = 'Show Scrollbars'

class MainWindow(QtWidgets.QMainWindow):
    def __init__(self, app):
        super().__init__()
        menu_bar = QtWidgets.QMenuBar()
        submenu = menu_bar.addMenu('&View')

        qaction = QtGui.QAction(TXT, self)
        submenu.addAction(qaction)

        qaction = QtGui.QAction(TXT_PLAIN, self)
        submenu.addAction(qaction)

        # Uncomment for correct text items:
        #qaction = QtGui.QAction(TXT_PLAIN + ' longer', self)
        #submenu.addAction(qaction)

        menu_bar.addMenu(submenu)
        self.setMenuBar(menu_bar)
        self.show()

        # Some debug output:
        fm = QtGui.QFontMetrics(QtGui.QFont())
        width = fm.size(Qt.TextFlag.TextHideMnemonic, TXT).width()
        width_mn = fm.size(Qt.TextFlag.TextShowMnemonic, TXT).width()
        width_plain = fm.size(Qt.TextFlag.TextHideMnemonic, TXT_PLAIN).width()
        width_plain_mn = fm.size(Qt.TextFlag.TextShowMnemonic, TXT_PLAIN).width()
        print(width, width_mn, width_plain, width_plain_mn)
        print(fm.elidedText(TXT, Qt.TextElideMode.ElideMiddle, width_mn,
                            Qt.TextFlag.TextShowMnemonic))

app = QtWidgets.QApplication(sys.argv)
win = MainWindow(app)
app.exec()

I've been playing around with elidedText manually, but everything works as expected and all the text length are the same, regardless of mnemonic. Here's the debug output:

108 108 108 108
&Show Scrollbars

Anyone knows what's up?

[SGaist]

Hi,

Looks fishy...

Which version of PySide6 are you using ?
On which platform ?

[le_becc]

I'm on Debian Linux+Gnome+XOrg. I'm currently on PyQt 6.2, but this has been happening in 6.1 as well, and maybe even 6.0. I don't remember exactly when I added this menu...

[SGaist]

Testing the same application with PySide2 does not exhibit this behaviour.

You should check the bug report system to see if it's something known. If not, please open a new ticket providing your script and finding.

[le_becc]

Thanks for the reply! I looked at the bug tracker before posting here, but I looked again and I was more lucky this time. Seems like it's this bug.