Issue: Permissions don't work for Firefox

[Ephellon]

Use this if Web to Plex doesn't run on any page, and you have Developer Mode enabled. Please use the table below to point to the error location.

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Describe the error
When enabling permissions for a site, Firefox does not update them asynchronously. I've tried adding waiting statements, but it does not like them.

To Reproduce
Steps to reproduce the behavior:

1. Go to Web to Plex (the website)
2. Click the Allow all permissions button
3. The page will refresh and prompt again

Estimated location
0U 0B 0P

Screenshots
If applicable, add screenshots to help explain your problem.

Extension Information

• Version: 4.1.2.2
• Source: store GitHub
• Browser: firefox

Additional comments
Add any other comments about the problem here, such as how often the issue occurs, any new changes, etc.

[Ephellon]

Alright, f**k Firefox... I found the problems: the var ... declarations that Firefox was whining about.

• v4.1.2.0 → let configuration...
  • Error: Redeclaration of configuration...
• v4.1.2.1 → var configuration...
  • OK
• v4.1.2.2 → var configuration... ← Up yours
  • Error: Message port does not exist
• v4.1.2.3 → let configuration... ← Why?
  • OK

Currently, it works as intended. let + init && init() when re-initializing