[Can't repro]Undefined is not iterable

[Twisted-Code]

Please confirm the following.

• I checked the existing issues for duplicate problems
• I have tried resolving the issue using the support portal (I didn't see any articles mentioning this error)

What browsers are you seeing the problem on?

Chrome (including Arc, Brave, Opera, Vivaldi)

Describe the bug

The first time this happened (I've not been able to repro it since) it was after I logged in -Having clicked the follow button on a project while logged out- and went backwards in my navigation history. I suspect something on the page may have gotten confused by the backwards navigation, which is a good example of why I normally try to avoid my navigation history after a state change as big as logging in. In this case though, it was justified since your login flow does not remember the page I was on before logging in.
Fortunately it seems refreshing the page is sufficient to clear the error.

Steps to reproduce

Uncertain, it only happened one time so far:

1. Start on a project page, while logged out. (I was on bountiful's overview)
2. click the "follow" button in the top right
3. since you started logged out, you will be prompted to login
4. in my case, I logged in with github
5. logging in put me back on the homepage, not the project I was out before, so I used my navigation history (I forget whether I walked for jumped back) to get back to the project page
6. initially the page loaded everything I expected to see
7. ... But then the error occurs partway through the load

Expected behavior

Finish loading the page if possible, ideally by avoiding the error rather than suppressing or handling it.

Additional context

Screenshot:

[Twisted-Code]

Since I'm unable to reproduce this at this time, feel free to close it, if you need to. I can always make a follow-up (and the impact of this issue seems minor to begin with since a page refresh solve it), I just wanted to at least document what happened the one time, since no other issues mentioned "undefined is not iterable".