According to https://secure.phabricator.com/book/phabricator/article/herald/ , "Mark with flag: Flag the object for later review. This action is only available on personal rules." As we've disabled Herald for the time being (T493) this is not an option. Hence we will drop personal tags and not try to migrate them somehow.

I'm not sure what the exact focus of this task is, but we should warn affected users to save their tags data. @Qgil: Does that require this ticket or could that be covered by T188?

Users can search for their tagged tickets via Bugzilla's Custom Search: ‹ Tags | match regular expression | .+// ›

In my opinion, we can choose this task as soon as the email mentioned in
the description is sent to the affected users. Is this possible and simple?

I've filed https://rt.wikimedia.org/Ticket/Display.html?id=8628 to get the email addresses of Bugzilla users who have used personal tags. SQL Query:

SELECT profiles.login_name FROM tag JOIN profiles ON tag.user_id = profiles.userid;

Hi andre__,

that query returned 153 rows but included quite some duplicates, so i added a "DISTINCT" to filter them out and these 66 are left then:

mysql:root@localhost [bugzilla]> SELECT DISTINCT profiles.login_name FROM tag JOIN profiles ON tag.user_id = profiles.userid;
+------------------------------------+
Hide quoted text

..

data pasted on the RT ticket, wasn't sure if i should paste the email addresses here.

• Daniel

Thanks to mutante I got the email addresses of those 66 affected Bugzilla users having set 153 tags.
Email to send out - something like this? Feel free to change/improve/clarify/dramatize:

<snip>

Save your personal "Tags" in Wikimedia Bugzilla

Hi,

we are contacting you because you have used Wikimedia Bugzilla's "Tags" functionality.

Wikimedia will soon migrate from Bugzilla to Phabricator.
While most Bugzilla data will be converted, Phabricator does not offer any functionality similar to Bugzilla's personal "Tags".
Hence your data in "Tags" will get lost soon.

You can find all Wikimedia Bugzilla tickets that you have tagged by visiting this URL:

https://bugzilla.wikimedia.org/buglist.cgi?f1=tag&o1=regexp&query_format=advanced&v1=.%2B

Cheers,
andre
</snip>

I saved the text in the editable task description, just changing a couple of emails.

That email deserves a more official signature, even if it is fair to assume that whoever knows what are personal "Tags" also knows who is andre. :)