Difficulty resetting key phrase

When I first created my account, I did not use a very strong key phrase. So I requested a "password reset" link (which should really be "key phrase reset"). When I tried creating a stronger phrase, I kept getting the following error

```
Server failure: CSRF-token verification failed for post
```

I assumed this was because the phrase contained invalid characters, so I tried several variations and continued to get this error. Eventually I found a strong phrase variation that was accepted.

No repository files or tests are identified. Start by reproducing the key-phrase reset flow and tracing the CSRF-token verification failure; done means a valid stronger key phrase can be submitted without this error, and the reset terminology is addressed if included in scope.

Written by the indexing model from the issue text.