closes #7550

closes #7580

And cleanup old reshares with deleted root posts

closes #7578

closes #7576

Fixes #7424

closes #7575

closes #7568

Fixes #7563

closes #7566

closes #7565

closes #7579

This was in all stack traces, which confused people ...

We currently only support IE11, so the version check was already old
again ...

When we break old browser versions, we don't check that for other
browsers. So older IE browser just break, like very other older browser
too.

closes #7557

This was needed for IE8 and IE9

Was needed for IE8

closes #7571

closes #7570

Also add "it" as fallback for "oc" and "sc"

The user_email is the first field anyway, and login form as a
user_username field too, so it maybe happens that we already fill in the
user_username filed there before page load finished.

closes #7556

closes #7551

closes #7530

closes #7554

closes #7548

closes #7547

closes #7546

closes #7545

closes #7544

closes #7543

closes #7542

Fixes #7541