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Oh, well it depends where you have mounted your drives on.
you can do that in your file browser, your partition manager or via console with lsblk
.
Gnome Disks:
File Browser:
Console:
and add them in the file access list under “Other files”.
(I have installed steam directly so OBS had to act as a stand in)
restart Steam so that those new permissions can be applied.
Presto was nice. But I guess being quite strict about standards was just too much to handle for the chrome fanboy developers.