Backports to release 1.12.4

[dkarrasch]

• In-place multiplication of Diagonal with OffsetMatrix should throw #1526

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.72%. Comparing base (7923683) to head (92a692d).
⚠️ Report is 3 commits behind head on release-1.12.

Additional details and impacted files

@@               Coverage Diff                @@
##           release-1.12    #1527      +/-   ##
================================================
+ Coverage         93.70%   93.72%   +0.02%     
================================================
  Files                34       34              
  Lines             15477    15479       +2     
================================================
+ Hits              14502    14508       +6     
+ Misses              975      971       -4     

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