When I try to use HTML 5 App cache functionality for my salesforce softphone its working in chrome. I am basically caching my static resurce files.But the same is not working in IE11.I am getting this error "Resource doesn't exist on the server: AppCache Fatal Error ".Do I need to do anything specific for making this to work in IE11?

Instrustions from Trailhead:


Here is what I did (I used copy/paste for each line, so I know that it is identical to the example):


When I try to save, I am give this messege:


Ok, the example on Trailhead didn't tell me to do this, but I make the chage as requested:


Now I recieve two new errors when trying to save:


Clearly, my line 4 ends in </p> as it should, so the errors do not make sense.
This part of Trailhead appears to be broken and is holding back my progess (15 minute module? Ha, try an hour of banging your head against a wall, giving up for a month and a half and then returning with fresh eyes and fresh resolve only to beat your head against the same wall for another hour).

Any help would be greatly appriciated!

 

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