If you want to standardize @ example.com as the official domain for examples that's fine with me, however, doing a bit of Ctrl + F on the documentation page I can see that:

• amLoggedInAs has 'john_doe@gmail.com',
• fillField has 'jon@mail.com', (this one comes from InnerBrowser, so you'd have to send a PR there to change it).
• grabSentEmails has 'john_doe@user.com',
• submitSymfonyForm has 'john_doe@gmail.com'.

Please update them all to be able to approve and merge this PR.

There you go - I hope I got 'em all :-)

BTW: For changes like this, it would be really handy to have a direct link from each function on the docs page to the source code, as I suggested at Codeception/Codeception#6063 (comment)
What do you think? Who could add this? @Arhell too?

For changes like this, it would be really handy to have a direct link from each function on the docs page to the source code

I know what you mean. But the symfony module is currently the only one that has traits for functions, so this change would only be for this module.

Previously only this:

was enough because all the documentation was in the same file, but this is no longer the case.

Who could add this? Arhell too?

Are you in the Slack of Codeception? Sadly I don't have an answer for that either.