Comment # 23 on bug 1027691 from Wolfgang Bauer

(In reply to Josh Zimmerman from comment #21)
> Worked under Plasma5 session login also. Thanks :) The way I feel about all
> this is that there is no reason to take away functionality just because
> something is old like I recall one time I had to recompile the Kernel just
> to turn on Parallel Scanner support.

We did not take away functionality. Qt just does not support SSE1-only CPUs any
more in Qt5. Adding that would mean to rewrite the Javascript JIT engine from
scratch and maintain two completely different versions.
The Qt developers are not willing to do that.
See also the discussion here: https://bugreports.qt.io/browse/QTBUG-35430

The only option is to actively disable the JIT engine on build time and only
use the run-time interpreter, which is of course slower, but you also need to
patch it to not abort if it detects SSE2 missing.

As I wrote, I do not know why that patch got removed in our package, I'm
actually not really involved in Qt packaging.

The patch does have a downside though: the lib needs to be compiled *twice*,
with and without SSE2, to not cause performance degradation on 32bit systems
with SSE2 support (including 32bit apps on 64bit systems).

(In reply to Josh Zimmerman from comment #20)
> I think you should include this in the stable release if it works for more
> than just me. 

I think your confirmation is sufficient, I noticed that Fedory does still have
basically the same patch in their latest qtdeclarative package (they remove the
error message completely though).

I submitted the "fixed" package to the devel project, let's see if it gets
accepted.
https://build.opensuse.org/request/show/494707

(In reply to Josh Zimmerman from comment #22)
> Until I did a distribution upgrade. It quit working for some reason.

Running "zypper dup" will reinstall the original version included in the
distribution (which requires SSE2).

You should be able to lock the package ("Taboo" in YaST or "zypper al
libQtQuick5") to prevent that.

Or add the posted link as repo, with a higher priority if you want to be
"safe".