Dash.js: Reference Client v3.0.0 page broken in Internet Explorer 11

[mattlohkamp]

Environment

• [x] The issue observed is not mentioned on https://github.com/Dash-Industry-Forum/dash.js/wiki/FAQ
• [x] The issue occurs in the latest reference client on http://reference.dashif.org/dash.js/ and not just on my page
• Dash.js version: 3.0.0
• Browser name/version: Internet Explorer 11 (v11.418.18362.0)
• OS name/version: Windows 10 (v10.0.18362)

Steps to reproduce

Navigate to Dash JavaScript Player Version 3.0.0 in Internet Explorer 11

Observed behaviour

javascript syntax error leads to broken page UI, leaving the page unusable

Console output

SCRIPT1004: Expected ';'
ControlBar.js (353,25)
SCRIPT1002: Syntax error
DownloadRatioRule.js (55,45)
ReferenceError: 'ControlBar' is undefined
   at Anonymous function (http://reference.dashif.org/dash.js/v3.0.0/samples/dash-if-reference-player/app/main.js:341:5)
   at invoke (http://reference.dashif.org/dash.js/v3.0.0/samples/dash-if-reference-player/app/lib/angular/angular.min.js:41:386)
   at Anonymous function (http://reference.dashif.org/dash.js/v3.0.0/samples/dash-if-reference-player/app/lib/angular/angular.min.js:89:428)
   at p (http://reference.dashif.org/dash.js/v3.0.0/samples/dash-if-reference-player/app/lib/angular/angular.min.js:65:122)
   at g (http://reference.dashif.org/dash.js/v3.0.0/samples/dash-if-reference-player/app/lib/angular/angular.min.js:58:481)
   at g (http://reference.dashif.org/dash.js/v3.0.0/samples/dash-if-reference-player/app/lib/angular/angular.min.js:58:498)
   at Anonymous function (http://reference.dashif.org/dash.js/v3.0.0/samples/dash-if-reference-player/app/lib/angular/angular.min.js:58:119)
   at Anonymous function (http://reference.dashif.org/dash.js/v3.0.0/samples/d

hope that helps!

[davemevans]

There are two issues here:
1) ControlBar is never transpiled and contains an await, which is not supported in IE11. Historically, this module has only included IE11-compatible code.
2) An untranspiled DownloadRatioRule is imported for some reason. This contains an =>, which is not supported in IE11. This could possibly be pulled in from the dahsjs object?

[nicosang]

1. find function of Array in PlaybackController is not supported in IE 11

[nicosang]

@mattlohkamp could you, please, take a look at my PR #3106 ?
@davemevans , I didn't modify DownloadRatioRule, it seems to work without modifications => yes, I'm a bit lazy! ;-)

Nico

[mattlohkamp]

yep looks that should fix the issue.

I was neck-deep in IE11 support land a month ago, I feel your pain - thanks for jumping on this!