It happened loading a big csv, with separators badly formatted, generating (I suppose) a huge number of columns.
Now each time I try to start OP, I have an heap size memory alert, followed by almost a freeze of the machine running it, since allocated memory is about 80% of total available for operating system.
I tried to identify guilty data (windows appdata dir), without any success, since all projects are almost same modification time and have just numeric names.
I was able to change data dir (-Drefine.data_dir) and restart a clean OR.
I have many projects which of course I urgently need to restore: how to do it?
You might also be affected by a bug that appeared to duplicate certain characters in the projects metadata in OpenRefine < 3.6 every time OpenRefine is opened.
In the ticket are some mitigation strategies on how to find affected projects and clean them.
These mitigation strategies will help you find the project that causes the problem, regardless of whether you are effected by the data duplication problem or not.