On ECL Watch, when you hover your mouse over the top most menu a pop-up descriptor immediately appears (Activity, ECL, Files, Published Queries, Operations) and blocks the tab buttons beneath them. This happens on at least HPCC 7.6.48-1
For example: The "Activity" pop-up descriptor gets in the way of clicking anything beneath it. Changes depending on the page, but Activity, Workunits Logical Files, Queries and Topology main tabs get blocked. This only happens if you mouse over, even quickly and in passing, over the ECL WATCH button/icon at the top left.
Fix: Perhaps a timer so you have to hover over for a few moments before the descriptor to popup.