+1000 for the cache issue. Better yet try in private mode. Device join does fail on simulator, I reported that looong ago to airconsole... There are different hacks possible to overcome that and I like your onConnect idea, but then again, once uploaded it won't fail anymore. Same for the simulator connect/disconnect buttons, they do what they want, not what you expect. Then, the simulator highly depends on the browser, I had 0 chance running it on edge, works 50% on chrome....
I'd say that in the actual state I won't try to debug that, imo the problem lies on the simulator. I should make my new plugin public in about 2 weeks and we'll see then... The new one cleans the mess with message key and stuff per Exemple. I should meet with airconsole on Feb 26th, I'll have a word concerning that issue