It seems that you're using an outdated browser. Some things may not work as they should (or don't work at all).
We suggest you upgrade newer and better browser like: Chrome, Firefox, Internet Explorer or Opera

Killing all python processes got Origin working, but Steam still refuses to work. This makes me wonder, what is the state of the API? Are the processes not required to register themselves with the client? I don't know what needs work, but it could be the API, the API behind-the-scenes, or the plugin as my prime suspects. These processes should be required to register themselves with the client, so that when the client is exited, it can make process cleanup part of its cleanup as opposed to letting these processes run wild on the system. The API needs to be strict in requiring registration and actually doing its job of cleaning up these processes.

At the same time, the plugin needs to avoid any dirty tricks to get its job done, and do a good job managing its own resources. That last part is probably moot given it's python, but there are a lot of moving parts in motion here, and one rogue part can bring the whole thing down.

I don't leave my launchers open in the background, which means I can be opening and closing them a couple times a day. It certainly adds up over the course of a month.
Killing processes didnt solve the steam issue here. Still crashes after 30 seconds to a minute.
I am having the same issue. Only the Steam plugin is crashing. I have reinstalled GOG 2.0 but it didn't help. There are no longer Python processes to end so I am not sure what else to do. I have submitted a bug report but have not heard anything back.
Jumping onto this bandwagon. If I had to guess, I'd say it's related to achievements.

896d43afa4f8\", line 23, in <module>
import achievements_cache
ModuleNotFoundError: No module named 'achievements_cache'

That's what I'm getting in my steam plugin log. There's more in it, but it looks like this is where it ends.

The client log repeats the startup, stop, and crash of the steam plugin.