Community VisualForce Page Not Working In Mobile

Question

I am getting this error page when viewing the VF page on a mobile device (both IOS and Android) after logging into the Community. It's not a FLS Permission Issue because the page works flawlessly on Desktop following the exact same steps. The Community User Profile also has access to the VF Page.

URL Description: https://base_url.csxx.force.com/community_name/s/page_name?param=record_id

Any ideas on why this is happening or how to resolve for mobile?

Much appreciated!

(related question)

I have already validated the following: Setup > Visualforce Pages > navigated to the page in question > Security > validated both Community Profile & Community User Profile are enabled. I also validated the page has the checkbox for 'Available for Lightning Experience, Experience Builder sites, and the mobile app'.

Answer 1

My Resolution: I found this question that was helpful.

To add the error message to this page you do the following. Setup > All Sites > Workspaces > Administration > Pages > Go to Force.com > scroll down to 'Error Pages' section > click 'Exception' next to 'Generic Error Page' > Edit > add the following highlighted lines: Then set up a debug log on your test user to get more information on the error. In my case, my error was 'NULL POINTER EXCEPTION' because I was attempting to reference the following: ApexPages.currentPage().getHeaders().get('referer').substringAfter('?param='), when 'referer' was null (see my other question for more information... this is null because referer is not in the headers when on a mobile device, this doesn't actually error in desktop).