Occasionally when your session expires or you change your password your existing sessions will expire. Normally, SKULabs can communicate that you need to sign in again and you'll be prompted to sign in.
On one browser, Microsoft Edge, Microsoft has decided to no longer allow us to read responses from our own servers when we send these unauthorized errors.
We do suggest using a modern browser that follows industry standard specifications like Chrome, FireFox, or Safari in the mean time. Microsoft continues to try to produce a standards-compliant browser but as we're seeing here they aren't quite ready.
You should be able to resolve any "Failed to read" error on Edge by signing out. If you're trying to sign in when you get this error, you probably have the wrong password but there is no way to tell on Edge currently until we work around this Edge limitation.