Yes, but all those services have the same main problem: a single point of failure. They also don't work offline. I believe that storing the issues in plain tex

Yes, but all those services have the same main problem: a single point of failure. They also don't work offline. I believe that storing the issues in plain text in git repositories synced across several git servers is more robust and future-proof, but time will tell. Having a simple storage format allows me to later on export it to any other service if I change my mind.