A Unity ID allows you to buy and/or subscribe to Unity products and services, shop in the Asset Store and participate in the Unity community.
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It's certainly possible. But the issue I've been encountering only appeared in 2019.3. That bug you linked has reproducibility since 2018.2.
I filed a bug report with Unity. Hopefully they'll get this sorted soon. Will post here if I find anything out.
I second this complaint. My C drive is a low capacity M.2, I do not have enough room to install the 2 dozen Unity installs that I usually have on...