Am 06.04.18 um 11:51 schrieb Patrick Dunford:
If you expect to double click a project file and Qgis opens, then only
one version of Qgis can be registered for .qgs file extension at a time.
True, but you can switch that at any time:
You can create links to the variuos .reg files on your desktop and
switch to 3.0 and back with one click.
I am sure this is the same on most OSs.
On Linux, you can't even install several versions in the same OS
(without using a virtual box guest system).
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