If i visit a deleted flow topic (at least with a non-privileged account), e.g. https://www.mediawiki.org/wiki/Topic:Sd3qkquvywwoib5y, i see the following:
The message key doesn't exist.
For info the qqx:
We should check what we're supposed to be showing here (probably the deletion log?) then show a valid error message.
Related to this, @demon spotted the following PHP warnings in prod (message taken from Task T90910: Undefined variables (type, start) in Block/Topic.php:
Spotted in production with 1.25wmf19:
2 Undefined variable: type in /srv/mediawiki/php-1.25wmf19/extensions/Flow/includes/Block/Topic.php on line 816 2 Undefined variable: start in /srv/mediawiki/php-1.25wmf19/extensions/Flow/includes/Block/Topic.php on line 816