I have a very simple workflow that launches the Trello app (not the website!). You can find it here: https://drive.google.com/file/d/1zhqdM3A_7UMDiiEVCmZYVwLGWJChX3sV/view?usp=sharing
Note that it toggles visibility for the app. But if you open two windows in the Trello app, using the workflow to hide and then show the app will always switch to make the first-opened window frontmost, not matter which window was frontmost when you hid. Doing the same hide/show from the "Trello" system menu does not exhibit this behavior.
Any ideas what's going on here?