[Development] Qt6/Qt5 coinstallability (Linux distributions)

[Kevin Kofler]

Thiago Macieira wrote:
> But I've just remembered that Designer loads plugins and those are quite
> clearly tied to the Qt version. The file format is backwards compatible
> and has remained so for a few years. It is possible that the plugins
> generate the same XML regardless of version, but I think we shouldn't risk
> it. So yes, Designer should be versioned.

I think it would be much safer to just version everything.

Just remember Assistant in Qt 4, where early 4.x releases shipped an 
Assistant that was essentially compatible with the Qt 3 version, but it was 
later renamed to assistant_adp (and later dropped from the Qt distribution 
and shipped as an unmaintained separate legacy tarball) and a new 
incompatible Assistant (the QCH one) was introduced.

        Kevin Kofler