We have TAZ6 and were having issues with very very very laggy Cura installations on multiple computers. It seems that our issues were unique and most people are fine with their Cura LE 3.6.31. Writing this post in the hope it will help someone else.
It seemed that there were some particular machines that despite lower specs were doing much better with slicing. We tried the usual solutions, cleared cache, did clean installs, and sometimes the software was working OK, but on most machines, it was just unusable. Our computers are made for image processing and our issues were not due to lack of resources. We are connected to a large company network, our Windows 10 computers are bound to a domain.
I recently installed Cura on a new computer and Cura was flying, I was even able to use the layers view, or not have to wait 5 min for it to load. Last night Windows updated itself and Cura got super slow again. I once more checked what others tried and found references to disabling certain plugins Cura running super slow on a really good computer - Ultimaker Cura - Ultimaker Community of 3D Printing Experts
I went to the Menu, Plugins, Installed Plugins, and disabled a bunch of things I don’t use: Mirror Tool, Model Subdivider Plugin (Experimental), OctoPrint connection, UM3 Networking Connection, and UserAgreement, and the results are spectacular. The UM3 Networking Connection seems to be the biggest troublemaker. I confirmed it working on 3 different workstations.
If you have weird issues like the above and the usual steps don’t solve your issues try disabling some of these plugins.