INVALID_STATE_ERR: DOM Exception 11

[xosofox]

engine.io-client/lib/transports/polling-xhr.js

Line 247 in 90f4d17

xhr.responseType = 'arraybuffer';

Looks like this line can be made responsible for creating an Exception in Android 4.x browsers.

Would it be an option to try/catch this one as well?

Unfortunately, there is no way to reproduce this right now - but we see it happening when logging users' JS client errors

[darrachequesne]

Well, I guess we could include it in the try .. catch above, but I'm afraid the client would not be able to correctly parse the message.

It seems the tests pass under Android 4.4 though: https://travis-ci.org/socketio/engine.io-client/jobs/309206559

[xosofox]

As said, I cannot reproduce this either - it is just coming up in our client JS logs.
I'm assuming that the clients fail to parse the message right now anyway...

I might try/catch it, roll it out and check with the logs again

[xosofox]

Update: I rolled out a "fixed" version with the offending line in a try/catch and I DO have less/no client errors of this type anymore. Interestingly, there are no other, "new" errors, so it looks like whatever happens with the messages then, seems to work fine.