Tested on Arch Linux and in an Ubuntu 16.04 LTS live session.

I am using an AMD Radeon R9 380 with the open source driver (amdgpu).

Please let me know if I can provide any more information to fix this.

The article that you linked does not explain how to switch to Radeon from amdgpu and my own research didn't yield any results either.

It probably wouldn't have been a good idea anyway since radeon seems to be geared towards older hardware that amdgpu does not support (at least from my understanding).

Anyway, I also came across this thread (https://steamcommunity.com/app/269650/discussions/2/365163686043604822/) in the steam forums for the game where someone reported that the issue was fixed in a beta release that seems to be available on steam.

Do you know when/if this new version will be available on GoG?

I have the same issue here.
I've tried to change resolution or quality but no changes.

Nope. I also tested it on Ubuntu.

My guess would be that it is some weird interaction with Mesa (the open source OpenGL implementation). That would explain why I haven't seen anyone with an Nvidia gpu (with proprietary drivers) who has this issue.

Same here, Linux Mint 18, Radeon HD 3450 (is it considered above minimum requirements?), and I experience a lot of game breaking missing texts.

Nope, it is still broken for me.

Another user chiming in that the game is missing texts. Running Linux Mint 18

Cross posting from my own thread:

Good News! I got this fixed while trying to get Neoscavenger to work, so I don't know what did it for sure, so here's everything I did:

Uninstalled it

sudo update-pciids
sudo apt-get update
sudo apt-get upgrade
sudo apt-get install

*lots of trying to get neoscavenger to run through the terminal so I could track down errors*

sudo apt-get install libnss3:i386
sudo apt-get install ia32-libs-gtk
sudo apt-get flashplugin-installer:i386

(That last one probably didn't do anything)

*more attempts to get scavenger to work*

sudo apt-get install curl:i386

*get bored and goes to poke at dex again, reinstalling it and...what, I can see?!*

It's not perfect in the shops but it's working.

--

Check after each installation and for which works?

I didn't update the game, but it seems to work now on Arch Linux with Intel HD 4000. Not sure which system update did the trick, but there recently was a Mesa update (13.0), so maybe that's it ...