Metamask contentscript is injected on about pages when it should not be

[srirambv]

Description:

Metamask contentscript is injected on all pages when enabled

Steps to Reproduce

Scenario 1

1. Clean install 0.19.53/54/57
2. Enable metamask from extensions
3. Open a new tab and visit any site
4. Open dev tools, shows metamask content script injected (image 1)

Scenario 2

1. Clean install 0.19.53/54/57
2. Do not enable metamask from extensions
3. Enable 1password
4. Open the 1password background page by navigating to: chrome-extension://aomjjhallfgjeglblehebfpbcfeobpgk/_generated_background_page.html
5. Shows error in console for inject script (image 2)

Actual result:

Expected result:
Should only inject script where required

Reproduces how often: [What percentage of the time does it reproduce?]
100%

Brave Version

about:brave info:

Brave	0.19.57
rev	2d55158
Muon	4.5.4

Reproducible on current live release:

Yes

Additional Information

cc: @bbondy

[bbondy]

ok makes sense now, I was confused by the title, but after reading the description it makes sense.

[bbondy]

Scenario 1 is no problem by the way, updated steps with specific info about how to get the error for 1password background page.

[bbondy]

master: 27f4a4e
0.21.x: 010c0bd
0.20.x: 6e8dc88
0.19.x: 5484ba6