Random 500 errors when running CI4 on MAMP

Hello,
I'm rebuilding a dormant CI3 website on CI4. I use MAMP Pro v 6.7 (Mac OS Ventura 13.6). The app runs on PHP 8.2.
The issue I'm experiencing is very random. The pages load fine and then suddenly, while browsing the site, I get a server error 500. 
What's very unusual is that all I need to do is to make a small change to any of the files of the application (say add a new line break the main site model file), save it,  reload the page and the error is gone. 
Very often, when I notice that the page takes too long to load (leading to a 500 error), I make the same small change to any of the files,  save it, and the page reloads by itself and works fine.
I admit, I'm perplexed. 
Any insight will be much appreciated.