We mention about sponsorship in upgrade banner to non-business
organizations. The message for business organizations is same
as before.
There is no explicit hover behavior for banners for org types
other than business, as banners are not themselves links in
such cases and only parts of text inside the banner are links.
Fixes#22161.
We fixed the main issue of this form in CVE-2020-9444, but the audit
done at that time only included links found in rendered_markdown; this
change completes our audit for links with target=_blank anywhere in
the codebase.
It's a preliminary step to enable message_retention_setting in org settings
UI, which is a non-limited plan only feature. So we require a page_param
property that tells us the limited-plan state of the Zulip realm.