Backslash key not working

Librem 13v2 (UK keyboard) on Debian Buster

I somehow didn’t have the problem on Debian Stretch, but since I’ve installed Buster, my backslash / pipe key (between left shift and z) is not working.

At first, it was seen by the OS as the same as the hash / tilde key.
I saw those threads:

With the help of those threads, I now know what is happening behind the scene, and I edited /lib/udev/hwdb.d/60-keyboard.hwdb to comment out the purism block, added a 90-purism-backslash-hash-key-fix.hwdb file with this content:

 KEYBOARD_KEY_56=KEY_102ND  # The backslash key sends 0x56
 KEYBOARD_KEY_2b=KEY_BACKSLASH  # The hash sign key sends 0x2b

Ran systemd-hwdb update and udevadm trigger and…

Now the key just do not respond, it does nothing. Playing around by commenting/uncommenting out parts of the hwdb files doesn’t change a thing.

Why was I supposed to hunt for those informations ? Why is this not working in the first place more than 3 years after the first report of this problem ? Why isn’t this in the FAQ ? Or at the very least in a sticky thread or wherever it can be easily found ?
And why isn’t there a known, supported solution to this when the problem looks like it is known for years ?

I encountered a similar issue with the Librem 13v4 US keyboard using PureOS amber.

I posted my issue in Matrix and have reposted what I typed there. Maybe my workaround will work for you with some tweaks.

I’m not sure if anything broke recently but after installing some updates recently, I can’t use the key underneath the “Backspace” key to type a backslash or pipe on the US layout. My workaround is to add another input source and rearrange them so that my desired input source is second, which then allows the backslash/pipe key to work as intended.

I can’t tell if this is a recent bug or something I did to cause this.

Without the workaround, the backslash key types < for some reason.

This is for all programs from what I’ve seen: Firefox, Tilix (Terminal), Fractal - anything I can type text into.

I dug into this issue some more and there are old forum posts that describe this exact issue I recently encountered. I used to be able to use the backslash and pipe a few days ago until I did some OS updates and updated PureBoot to release 15.

I haven’t tried the workaround fixes described in the threads yet.

I’m using the Librem 13v4 US keyboard layout with the English (US) input source if that helps.

The updates I did could be red herrings but I’m not sure.

When I press the backslash key with the English US input source, it registers as the key to the right of the left Shift key.