RE: How to compile your very own Devcoin Wallet in Ubuntu 18.04 💪 💻 💾
Heads-up that error appears as of recently, so blockchain doesn't update properly - i.e. it's stuck at block 3999 (at first) if you just installed wallet by following this guide or some later block depending on your last receiver file.
To fix it, you need to manually download receiver files (e.g. from https://github.com/devcoin/receivers - apparently all receiver files, or https://galaxies.mygamesonline.org/receiver_files.zip which has only 80 files tho) and then put them inside your receivers folder e.g. ~/.devcoin/receivers
folder (you can only download the ones you are missing). Then restart the wallet and it should start syncing properly.
Some more discussion with regards to the issue:
https://bitcointalk.org/index.php?topic=233997.msg50510377#msg50510377