I've seen the same issue in Fedora. My workaround was to "sabotage" the org.freedesktop.Filemanager1 dbus service by creating ~/.local/share/dbus-1/services/org.freedesktop.FileManager1.service and changing the Exec line to e.g. /usr/bin/false or /usr/bin/true; this is better since it's persistent and isn't affected by system updates... etc. This makes Firefox use whatever file manager I set in ~/.local/share/applications/defaults.list (see comment #31).
Changing Exec to /usr/bin/dolphin somehow made "open containing folder" open the file manager, but the firefox UI gets sort of blocked/hung for a while, probably because firefox tries to query the capabilities of org.freedesktop.FileManager1 via dbus first, (just a guess).
(In reply to PhobosK from comment #36)
I've seen the same issue in Fedora. My workaround was to "sabotage" the org.freedesktop .Filemanager1 dbus service by creating ~/.local/ share/dbus- 1/services/ org.freedesktop .FileManager1. service and changing the Exec line to e.g. /usr/bin/false or /usr/bin/true; this is better since it's persistent and isn't affected by system updates... etc. This makes Firefox use whatever file manager I set in ~/.local/ share/applicati ons/defaults. list (see comment #31).
Changing Exec to /usr/bin/dolphin somehow made "open containing folder" open the file manager, but the firefox UI gets sort of blocked/hung for a while, probably because firefox tries to query the capabilities of org.freedesktop .FileManager1 via dbus first, (just a guess).
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