That's it! Thank you so much!

Just to be clear again:

Thanks anyway, but that doesn't fix the problem. I have tried it in another computer and the problem persist, which makes me think that this has something related with latest Windows updates.

Though this is not a support forum: 3D view > Properties-Panel (hit "N" in 3D view or View > Properties from the menu)

Yes I'm talking about poles. Could you tell me where I can find Rig Main Properties?

Just to be clear, we are talking about the IK poles, right?
[upper_arm_ik_target.R, upper_arm_ik_target.L, thigh_ik_target.R, thigh_ik_target.L, ...]

Created a new task for it https://developer.blender.org/T54803

Please follow our submission template and guidelines and make a complete, valid bug report, with required info, precise description of the issue, precise steps to reproduce it, small and simple .blend and/or other files to do so if needed, etc.

This three error messages comes by the way from this addon :)

Oh,my God! I just realized that I made a mistake. I replaced the top screenshot with the correct one. Sorry for the inconvenience.

Ah, i see. Many thanks :)

This warning is not related to that fix, it was introduced in master in rB0bbae3f3f659 and rB94b7bf3ec21b [which is not part of official 2.79x releases afaik] and just tells addon devs that bpy types such as menus, panels etc. should follow a strict naming convention [which obviously a lot of existing addons dont do...]

Sorry for resurrecting this thread. I have compiled the newest Blender version, and stumbled across that the fix has introduced a few error messages now at switching the libraries. The version included in 2.79b doesn't show this behaviour.

Yeah !! all right ! HERE measureit_main.py the good file to replace for 2.79b (1.7.0-> 1.7.1 measureit version) tabbed and spaces (for clean python writing).
Thank you so much for the fast (easy? / competitive) resolution for local measureit viewing !

Are you sure you are examining the same files in Windows/Linux compared to MacOS?

Ok, will proceed soon

Hi @stephen leger (stephen_leger),
think this is a reasonable fix, you want to commit yourself?

Thank you for the report. Currently we are aware of many issues in 2.8 and actively working to fix them. But since replying to reports takes time, we have decided to limit bug reports to module team members.

Please follow our submission template and guidelines and make a complete, valid bug report, with required info, precise description of the issue, precise steps to reproduce it, small and simple .blend and/or other files to do so if needed, etc.
A guideline for making a good bug report can be found here: https://wiki.blender.org/index.php/Dev:Doc/Process/Bug_Reports

regarding the xml error: I pushed rBA8d3301f66c77e7b5a1f310 now.
Closing the whole report as resolved then.

It is not as easy, on top of that 2.79 will currently only receive critical bug fixes.

@stephen leger (stephen_leger): ok, I have a fix, will push tomorrow...

Missing proper xml import
Never checked category stuff, i only made some cosmetic changes during 2.79 release process related to user defined library path and fixed temporary scripts path to writable folder.
Will probably require more in depth investigations of overall code, might take a look next week.

Even though the first issue seems fixed I can confirm the second ('xml is not defined')

It's reporting as 2.79.3 in the header, so I thought this was 2.79b; I'll ask them why their labeling is misleading. Apologies for the noise.