Hey, me again.
Another issue I've stumbled upon while using AlgoDEA is that sometimes (haven't been able to determine when, but it's almost always), if I select the Sender of a transaction using the "..." button, the Authorized Address and Authorized Mnemonic won't autocomplete - in fact, that dialog window will freeze and I'll have to kill my IDE (IntelliJ IDEA Community 2021.1 in my case).
Workaround:
Copy the address of the receiver and manually paste it in the "Sender Address" field, then change focus to another field. Doing that everything gets autocompleted alright and nothing freezes.