Hello there, @Jiwit - welcome to the Local community! 
This may be related to a bug that was recently uncovered:
Here’s what @austinwendt shared about it:
“I was able to do some troubleshooting and found that this is Windows specific, and like mentioned, only happens when using Apache. I have created a bug for our engineering team to take a look at, and I will keep this thread updated when we have the fix. Thanks for bearing with us!” - Austin
If it’s an option for you, you may want to try changing the web server from Apache to nginx, but before you do that I would absolutely recommend making a backup of your website!
You can create an export of your site by following these steps: https://localwp.com/help-docs/getting-started/how-to-export-a-wordpress-site-on-local/
Let me know if this helps,
Sam