Brave-browser: [Desktop] brave://discards is blank

[dentistformyeye]

Description

brave://discards should show information for each tab open in the browser and should allow for manual freezing/discarding of tabs, but a blank, white screen shows up instead.

Steps to Reproduce

1. Start the Brave Desktop app.
2. Go to DuckDuckGo in the current new tab.
3. Open a new tab and go to chrome://discards. On Brave, this will change to brave://discards automatically.

Actual result:

Blank, white page.

Expected result:

Reproduces how often:

Always.

Brave version (brave://version info)

Brave | 1.10.97 Chromium: 83.0.4103.116 (Official Build) (64-bit)
-- | --
Revision | 8f0c18b4dca9b6699eb629be0f51810c24fb6428-refs/branch-heads/4103@{#716}
OS | macOS Version 10.15.4 (Build 19E266)

Version/Channel Information:

• Can you reproduce this issue with the current release? Yes.
• Can you reproduce this issue with the beta channel? Haven't tried.
• Can you reproduce this issue with the dev channel? Haven't tried.
• Can you reproduce this issue with the nightly channel? Haven't tried.

Other Additional Information:

• Does the issue resolve itself when disabling Brave Shields? N/A.
• Does the issue resolve itself when disabling Brave Rewards? N/A.
• Is the issue reproducible on the latest version of Chrome? No. chrome://discards works normally on Chrome 83.0.4103.116 (tested on WIndows 10). OS might not matter though.

Miscellaneous Information:

chrome://discards is listed in chrome://chrome-urls on Brave Desktop (though not for Brave Android).

[srirambv]

This is a regression possibly on CR 83. I remember it used to work before. Thanks for reporting

[dentistformyeye]

I remember the bug existed as far back as Brave Desktop 1.8.XX (81.0.4044.129). I don't remember if the bug was in 1.7.XX (81.0.4044.113).

[jonathansampson]

This page fails to load completely due to the following errors:

Refused to load the script 'chrome://brave-resources/br_elements/shared_vars_css.m.js' because it violates the following Content Security Policy directive: "script-src chrome://resources chrome://test 'self'". Note that 'script-src-elem' was not explicitly set, so 'script-src' is used as a fallback.

and

(WEBUI context) extensions::safeMethods:20: Uncaught TypeError: Illegal invocation{TypeError: Illegal invocation
    at Object.define (extensions::safeMethods:20:22)
    at extensions::guestViewContainerElement:67:28
    at registerElement (extensions::guestViewContainerElement:56:28)
    at extensions::chromeWebView:220:1}