Created attachment 151657 [details]
Mentioned octave script

SUMMARY
Using Octave's plot function results in nothing being shown.

STEPS TO REPRODUCE
1. write an Octave script
2. use plot()
3. Run in cantor

OBSERVED RESULT
There are 2 cases.
- if plot integration is enabled, the cell is reported to be "calculating" forever, nothing is shown.
- if it's disabled, computation terminates straight away and still nothing is shown.

EXPECTED RESULT
Script tested in Octave, works as intended.

SOFTWARE/OS VERSIONS
Operating System: Fedora Linux 35
KDE Plasma Version: 5.25.4
KDE Frameworks Version: 5.96.0
Qt Version: 5.15.2
Kernel Version: 5.18.18-100.fc35.x86_64 (64-bit)
Graphics Platform: X11
Processors: 8 × Intel® Core™ i7-8550U CPU @ 1.80GHz
Memory: 15.4 GiB of RAM
Graphics Processor: Mesa Intel® UHD Graphics 620
Manufacturer: Dell Inc.
Product Name: Inspiron 5570

ADDITIONAL INFORMATION
See and test the attached script.
After investigating suggested related bug reports, I found out that changing the Octave backend from the default "octave-cli" (yes, this is still the default) to "octave" or even "octave-6.4.0" makes plots appear. 
Still, disabling plot integration makes plots disappear again.