Slow startup of Thunderbird beta

I have the latest TB beta running under windows 10 and I experience very slow startup times (several minutes).
When I compose a message, when I type the address the auto-completion is very slow.
Do you experience the same ?
I also use Thunderbird beta on MacOS and I have no problems

beta running under windows 10 and I experience very slow startup times (several minutes) … on MacOS and I have no problems

This suggests the cause is coming from Windows. See

Sorry but I think that the end of the answer is missing

Working on Mac but failing in Windows suggests the cause is coming from Windows. See

Works fine on my Windows.
Maybe check the SMART data for your drive or check the Task Manager to see what part of your PC is being maxed out when you start Thunderbird.