Steam crashes on 21.04

Turns out this is a bug in steam, which is currently (as of 28/06/2021) only available in the beta builds of steam client. You need to launch steam to switch to the beta builds, and when it doesn't launch, that's tricky. So for the moment, do the following:

  • Run steam --reset
  • Login to steam
  • If you use "family view" you may need to enter your pin
  • In steam, go to Steam menu -> Settings -> Beta participation -> Change button
  • In the "Beta Participation - Steam" window, change Beta participation drop-down from "NONE - Opt out of all beta programs" to "Steam beta update"

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  • Click OK

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  • Restart steam.
  • Steam will download an update

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  • Steam will re-launch, into the beta.

Everything should work at this point. Feel free to opt back out of the beta once the above bug is in the stable release of steam client.