Dear, today I noted that frituur-heidi.be/panel gives me a blank page after filling in my credentials and trying to logon. It worked before, for months, even a couple years now. A few days ago I used the panel to made some content changes to the website, so it definitely worked a couple days ago. I didn’t changed anything on the server the last weeks. So no clue where to start… other topics concerning this subject didn’t help me.
Kirby 2 doesn’t support PHP 8.x, support for Kirby 2 ended on December 31, 2020. If you want to use current PHP versions, you would have to upgrade to Kirby 3.