Per feedback from certain users regarding the removal of the User Task Report in 18.1, I have designed the following standalone app which should work in most environments, is geared towards admins (or users with "designer" privs and appropriate permissions to process instances), which creates a new "Reports Tab" report to reveal tasks for any arbitrary active user. The report offers quick access to the task itself as well as to the process instance.
Update: This tool has now been added to the AppMarket. If anyone has used it and likes it so far, please go to the AppMarket listing and give me a star rating or 'like' :)
The following app package is all-inclusive, except for certain Appian Common Object rules which I'm including in a separate patch. (Updated version: renamed to "Advanced User Task Report".)
8875.Advanced User Task Report (18.1 - 2018-07-23).zip
Update: 19.3 version using the new read-only grid and other enhancements:
Advanced User Task Report (19.3) - rich text grid updated (v2).zip
The needed Appian Common Objects, for environments which don't otherwise already have them (this would need to be imported first):
4010.Admin User Task Report - Appian Common Objects Patch (18.1 - 2018-05-29).zip
Discussion posts and replies are publicly visible
For anyone who's interested, I've created an updated version of this app to change the name to the (less confusing [i think]) name,
"Advanced User Task Report".
I am attaching the updated app package with the renamed components.
Advanced User Task Report (18.1 - 2018-07-23).zip