Most of the time I open .sla scribus files ("application/vnd.scribus" mimetype) with Scribus application, but sometimes I have to edit them with Geany (.SLA files are a kind of flat XML files). I do find Geany in the rightclick > other apps menu. Fine.
BUT after editing a .SLA with Geany once, Geany is set to be the new default application. I don't want this.
How can I set Scribus to be the real and only default application to open .SLA files and never have Geany replace it?
I've searched and tried various threads, but I could not find any applicable answers.
The OS is Ubuntu 18.04.01 (Bionic Beaver).