Installing chromium-browser on Octopi for TouchUI

Hi guys,

I've set up OctoPrint via octopi image 0.18.0 on a RaspberryPi 4 8GB.
Printing works fine, but I have a 7" touchpanel attached to the pi, that I want to use to display the touchUI version of the OctoPrint interface.

What is the problem?

I am not able do install chromium-browser to display the touchUI. When I hit sudo apt-get install chromium-browser I get the following errors:

Reading package lists... Done
Building dependency tree       
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 chromium-browser:armhf : Depends: libcups2:armhf (>= 1.7.0) but it is not going to be installed
                          Depends: libgtk-3-0:armhf (>= 3.19.12) but it is not going to be installed
                          Depends: chromium-codecs-ffmpeg-extra:armhf (= 84.0.4147.105-rpt2) but it is not going to be installed or
                                   chromium-codecs-ffmpeg:armhf (= 84.0.4147.105-rpt2) but it is not going to be installed
                          Depends: libraspberrypi0:armhf but it is not going to be installed
                          Recommends: chromium-browser-l10n:armhf but it is not installable
E: Unable to correct problems, you have held broken packages.

Additional information about your setup

Linux octopi 5.4.72-v8+ #1356 SMP PREEMPT Thu Oct 22 13:58:52 BST 2020 aarch64, OctoPrint version : 1.4.2, OctoPi version: 0.18.0, Raspberry Pi 4 8GB

How do I solve this? The download page of the octopi image 0.18.0 says its highly experimental. I hope this is not a problem of octopi 0.18.0 image itself.

Have you installed a desktop?

I followed this guide to install Desktop

After rebooting the display showed no longer the terminal Screen. Instead it displayed a black screen with a single white underline in the upper left corner.

Might be a bug on the 64 bit version - use the 32 bit one for now, iirc it's been mentioned already on the OctoPi repository.

Is it possible to switch my current installation to 32 bit?
If yes, how can I do that?

It is a reinstall of the SD card, using the 32bit image.
You can create a backup of OctoPrint first, re-flash the SD card then install 32bit, then restore the backup. I now can't find the comment about the issue you have, but I'm sure it sounds familiar. It will be here somewhere...

Thank you, that was the trick.

I was able to install everything I need with the 32bit version.