Web App capable mode doesn't work on login

I added this to my website head tag:

<meta name="apple-mobile-web-app-capable" content="yes">

And it works fine, until a user logs into the simple website user system I created. At this point, a permanent header and footer taskbar is shown and will disappear.

The top header has a button (in Hebrew, it reads "סיום" which is probably "end" or something similar in the English iOS version) which will allow the user to log off, and which I did not program at all.

How can I keep the full screen fell even if a user logs into his account on my website?

Web App capable mode doesn't work on login
 
 
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