EW & MAS: Clicking 'Create Account' fails on the welcome screen when using MAS

[wrjlewis]

Steps to reproduce

On a MAS enabled server (beta.matrix.org for instance)

Open Element Web
See 'Welcome to Element' screen

Click 'Create Account'
See error message

Outcome

What did you expect?

To be able to create an account following this flow

What happened instead?

You get an error message

There are probably two things to consider:

1. What should be the correct flow long-term, ie there are a couple of screens in the working flow that have sign-in and create account. The bug only happens if you click create account at the first opportunity / screen. If you click Sign In first rather than Create Account, then it works.
2. A short term fix to get it working for now

Operating system

No response

Browser information

No response

URL for webapp

No response

Application version

No response

Homeserver

beta.matrix.org

Will you send logs?

No

[wrjlewis]

In terms of priority: the short-term fix is fairly urgent as it prevents users (when following the flow mentioned) from registering new accounts on beta.matrix.org or where-ever else we want to enable MAS.

[daniellekirkwood]

@langleyd Can we get eyes on the short-term fix? Who is the best person to support this?

@element-hq/design Do we already have a plan for the long-term fix designed?

[americanrefugee]

@element-hq/design Do we already have a plan for the long-term fix designed?

Yes

[americanrefugee]

Also, here's the vision for MAS

[ara4n]

my suggested short term fix would be "if create user view errors, redirect the user back to the signin view".

[sandhose]

Fix on the Synapse side to make sure we return a sensible error: element-hq/synapse#17661

[t3chguy]

Duplicate of #6847