Navigation sporadically breaks CSS

[jacrys]

Issue: upon navigating back and forth rapidly, Github CSS completely breaks, leaving unformatted content.

Repro steps: have some history built-up in the tab, then go back and forward a few times, the request will break, and all css and some js seems to be blocked.

Environment: FF62.0b15 on Windows 10 Version 1803 Build 17134.165 using Codesy.io 0.0.1.0 (Codesy.io only enabled extension)

Troubleshooting completed: disabled all other extensions, testing repro steps until problem recurred. initially limited to Github extensions since issue only occurs on Github. eventually narrowed down to Codesy.

Console dump example when error occurs:

Content Security Policy: Couldn’t process unknown directive ‘https://www.codesy.io’
Loading failed for the <script> with source “https://assets-cdn.github.com/assets/compat-f849c975b0ffaa01d6ca305e48417d08.js”. wiki:705
Loading failed for the <script> with source “https://assets-cdn.github.com/assets/frameworks-ed54e8497dedd2e9d96d3f36144573c8.js”. wiki:706
Loading failed for the <script> with source “https://assets-cdn.github.com/assets/github-fc1376c13b536381fbf3e3a9764501ca.js”. wiki:708
Content Security Policy: The page’s settings blocked the loading of a resource at https://assets-cdn.github.com/assets/frameworks-0603882e6b9840d86c616b357dcbbdad.css (“default-src”).
Content Security Policy: The page’s settings blocked the loading of a resource at https://assets-cdn.github.com/assets/github-83814ad7ce1fb4ad37b7b5dd796c676b.css (“default-src”).
Content Security Policy: The page’s settings blocked the loading of a resource at self (“default-src”). Source: padding-left: 2px;. wiki
Content Security Policy: The page’s settings blocked the loading of a resource at self (“default-src”). wiki
Content Security Policy: The page’s settings blocked the loading of a resource at self (“default-src”). Source: margin-right: 2px;. wiki
Content Security Policy: The page’s settings blocked the loading of a resource at self (“default-src”). wiki
Content Security Policy: The page’s settings blocked the loading of a resource at https://assets-cdn.github.com/images/search-shortcut-hint.svg (“default-src”).
Content Security Policy: The page’s settings blocked the loading of a resource at https://assets-cdn.github.com/images/spinners/octocat-spinner-128.gif (“default-src”).
Content Security Policy: The page’s settings blocked the loading of a resource at https://avatars3.githubusercontent.com/u/3784287?s=40&v=4 (“default-src”).
Content Security Policy: The page’s settings blocked the loading of a resource at https://assets-cdn.github.com/assets/compat-f849c975b0ffaa01d6ca305e48417d08.js (“default-src”).
Content Security Policy: The page’s settings blocked the loading of a resource at https://assets-cdn.github.com/assets/frameworks-ed54e8497dedd2e9d96d3f36144573c8.js (“default-src”).
Content Security Policy: The page’s settings blocked the loading of a resource at https://assets-cdn.github.com/assets/github-fc1376c13b536381fbf3e3a9764501ca.js (“default-src”).
Content Security Policy: The page’s settings blocked the loading of a resource at self (“default-src”). Source: display:none;. wiki
Content Security Policy: The page’s settings blocked the loading of a resource at self (“default-src”). wiki
Content Security Policy: The page’s settings blocked the loading of a resource at self (“default-src”). Source: display: none; outline: none;. wiki
Content Security Policy: The page’s settings blocked the loading of a resource at self (“default-src”). wiki
Content Security Policy: The page’s settings blocked the loading of a resource at self (“default-src”). Source: width:360px;. wiki
Content Security Policy: The page’s settings blocked the loading of a resource at self (“default-src”).

During one refresh cycle I did get another error in console, no other errors appeared at that time:

Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at https://api.github.com/_private/browser/stats. (Reason: CORS request did not succeed).

Below is a screenshot of the error.