PhpStorm losing Git Changes | Ubuntu Guest in VirtualBox with Windows Host and Samba shared folder

Heyo!

Setup:
I've setup Ubuntu 22.04.4 in a virtual machine via Virtualbox 7.1.6 on a Windows 10 host and a shared folder with samba. Git is also installed on both operating systems.
My projects are running in Ubuntu and I'm opening those with PhpStorm on Windows. I'm also using GitToolBox plugin inside of PhpStorm, but did not make any big changes to the configuration.

Behaviour:
When making changes via PhpStorm it detects the changes like usual, the file turns blue and the line in the file is also marked blue - all good. But as soon as I click outside of the current file, something will automatically unmark the changes and PhpStorm “thinks” the changes are no changes anymore. See the following pictures as reference:

after the previous screenshot PhpStorm automatically displays like this. no commit, no push happened meanwhile, but all blue marks are gone somehow.

“Git status” in terminal on windows and ubuntu does give the correct status, only PhpStorm won't recognize the changes anymore.

I do know that this or a setup alike should work, as I've worked in a company before with that kind of setup of using a shared folder between windows host and ubuntu guest and there git inside of phpstorm was working just fine. Now I've this weird behaviour and don't know what the cause could be.

I've searched online for solutions, but nothing has helped so far. Am I lacking a certain configuration or is this setup just not possible in general? If it is the latter, what the heck have my old colleagues made to have this working? Unfortunately I lost contact and can't ask them.
I appreciate any help!

Some configruation info:
Network adapter in Virtualbox is set to bridged mode.

Samba Configuration for the shared folder:

[projecttest]
path = /var/www/html
public = yes
writeable = yes
guest ok = yes

windows user and group, as well as ubuntu user has the same name: projecttest.

If JetBrains support sees this I've also uploaded a video: Upload id: 2025_03_19_28bTq2jym7ho1b9NrNs2Fx (file: PhpStorm Git Issue on samba share.mp4)

If more information is needed, just let me know.
Thanks in advance for everyone helping out!