@sgunhouse TX for your effort, but I still couldn't solve it 😓
Added the following code line in the head-section:
<link rel="apple-touch-icon" href="favicon_57.png"/>
and put the file in the root folder of the website, so right next to the index.php file.
Also cleared history etc from the phone's opera-app but ...
Screenshot_20200823-152038.png
