Upgraded to 21.04 and now software (ODADrawingsExplorer) is broken

[Colin Watson]

On Wed, Jul 07, 2021 at 07:10:38PM -0400, Robert Heller wrote:
> The thing is, these people did something incredibly stupid when then built the 
> Debian package -- they did this pre-install dependency nonsense, instead of 
> proper dependencies, which would have caused apt to pull the proper 
> libraries automagically.

I generally find it best not to say that people have done something
incredibly stupid without (at least) first fully understanding the
problem myself ...

The problem here is not the use of Pre-Depends (they probably shouldn't
have done that, but it's not the problem here); apt can handle
Pre-Depends just fine.  The problem is that the qt5-default package
they're depending on doesn't exist after 20.10.  The changelog message
for its removal in Debian (which Ubuntu then inherited) was:

  * Remove qt5-default. Nowadays it's not needed as Qt 5 is the only Qt version
    in Debian and it brought more problems than solutions.

Since qt5-default was just a metapackage that depended on qtbase5-dev
and qtchooser (or similar depending on your Ubuntu version), it should
be straightforward for the maintainers of this package to depend on just
what they need from that rather than on qt5-default.  I wouldn't say
that they did something stupid - it may well have been reasonable at the
time, or at least not obviously wrong - but their packaging does need to
be updated now.

-- 
Colin Watson (he/him)                              [cjwatson at ubuntu.com]