This is what I mean by checkbox (simplified code to avoid all confusing stuff):
<ToolBar IsManipulationEnabled="False">
<Menu>
<MenuItem Header="Select file">
<MenuItem
Click="BtnOpenFile_Click"
IsChecked="{Binding IsFileSelected}"
Header="File"/>
</MenuItem>
</Menu>
</ToolBar>
Normally WPF checkbox appears as empty or ticked.
For me it appears empty when not ticked (as it should):
https://i.stack.imgur.com/wkPE3.png
Black square when ticked (as it shouldn't):
https://i.stack.imgur.com/eK5aN.png
Normal "tick" when ticked and mouse hovers above (as it should, but all the time):
https://i.stack.imgur.com/kmAr8.png
I'm not using any 3rd party libraries for UI, it's default WPF. Is there a way to fix it? I'm almost certain that black square part is a glitch.
What I have tried:
A lot of googling but no one offers direct working solution.