|Invalid||Tgr||T78191 Impossible to find Phabricator task from Mingle card|
|Invalid||Qgil||T78193 Links in the task description are not searchable|
Searching for "https://wikimedia.mingle.thoughtworks.com/projects/multimedia/cards/861" brings this task as single result. To me this means that links in the task description are indeed searchable, but for some reason some of the Mingle migrated tasks are not indexed yet. Resolving this task, although we need to keep an eye on the indexing of Mingle tasks.
Searching the exact title does work now both in the general search https://phabricator.wikimedia.org/search/query/c.iIS0BovE8j/#R and the search query you posted above (https://phabricator.wikimedia.org/maniphest/query/HCPzo9PC.qB9/#R). So some indexing seems to be happening.