I am struggeling to replay your Steps.
What I did:
1.-3.
After that I voted as the email owner. What do you mean with "register with the same email"?

After voting click Register

And use the same address you received the invitation on

Ahhhhhh. OMG. OK. You mean using the same share address after using it for initial vote. There is definetely a bug, but the bug is, that reusing the link leads to the register page and not directly to the poll.

The share link is the direct ticket to enter the poll.

The register method is the wrong address, since it is used to create a new share after registering and should only use the userId created there. Strange. I wonder why this leads to the registration page.

So if I understand correctly, the register button should only be shown for non logged-in users in public shares.
It shouldn't be shown for mail shares since an ID already exists (the email address )
Correct?

maybe currentUser can be checked and the button should be rendered conditionally ?

Should I update the Pr ?

I have to replay my memory. 📝

First use case

A public link is used and the user has to register. He then gets a new share token and will be redirected to the poll with the fresh created share.

Second use case

An external user is invited via mail or via contact (like mail but with the contact's name as display name) from the contact app.
In this case the user should be able to approve or change his email address and displayname first. I think this logic broke, when changing the workflow from first show the registration dialog to showing the poll without it and hiding the registration behind the register button.

I think I forgot to respect the second use case whan changing the workflow.

So changing the PR to quick fix that would be nice. Anyway, the userId is the email address, which is also not a good idea. It should be a gerneated id as well, since it is a personal public share.

But I am thinking about making next the main branch, once the vue3 migration is stable and think about a more robust change over there.

maybe currentUser can be checked and the button should be rendered conditionally ?

Checking the share type is more precise. Or at least the permissions delivered in the poll structure. The permission votemeans the user is allowed to vote.

It seems to do the job. But there is another problem. Changing the username or email address throws an error.

Seems, I mixed up something somewhere. 🙈

Hello @dartcafe, hope it's ok that I merged and leave the newly arisen problem to be tackled in a further PR!

OK for me atm. But I prefer the PR getting merged by the creator. Possible final action may be planned before merging.

At least the changelog is missing. But I will add it later.

/backport to next

The backport to next failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout next
git pull origin next

# Create the new backport branch
git checkout -b backport/3648/next

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts, resolve them
git cherry-pick 2d09af31

# Push the cherry pick commit to the remote repository and open a pull request
git push origin backport/3648/next

Error: No changes found in backport branch

Learn more about backports at https://docs.nextcloud.com/server/stable/go.php?to=developer-backports.

Backport to next is not possible, since it got a complete overwork.