Wow, two-factor authentication on websites without SMS is sure easy these days:
Why did I wait so long to do this? It's e-e-e-easy!
Ah, forgot step 5: save backup codes the site provides into your password manager. Or maybe set up more second factors.
Also, before you ask: yes, Mastodon supports 2FA: App Settings → User Preferences → Account → Account Settings → Two-factor Auth
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