🐞Safari Extension failing to load - Refused to load safari-web-extension:

Concise Description

First of all, I want to express my sincere appreciation for the work you’ve put into ImprovedTube. I am currently experiencing issues where the extension fails to load in Safari. I have already performed a clean reinstall and cleared my cache, but the errors persist. I hope that sharing these details might help in identifying the fix.

I am seeing a console error indicating that the core script is being blocked::

Refused to load safari-web-extension://[EXTENSION-ID]/js&css/web-accessible/core.js because it does not appear in the script-src directive of the Content Security Policy.

Also, I am seeing the following path errors in the Safari extension settings:

Unable to find "_locales/en_CO/messages.json" in the extension’s resources. It is an invalid path. Unable to find "_locales/it_CO/messages.json" in the extension’s resources. It is an invalid path. Unable to find "_locales/de_DE/messages.json" in the extension’s resources. It is an invalid path. Unable to find "_locales/es_CO/messages.json" in the extension’s resources. It is an invalid path.

Safari Version: 26.5 (21624.2.5.11.4)

The extension works perfectly on other browsers on the same machine.

Thank you for your time. I’m happy to provide any further logs or testing if needed to help.

Browser/s

Safari

Other Browser:

No response

'Steps to reproduce' - Which of our features is required for the bug to happen?

1. Install ImprovedTube from App Store. 2. Open Safari . 3. Open Youtube 4. Extension does not work

Since when?

Just Installed

Does the bug still happen when you log out of YouTube?

Yes

..No? Then please paste your yt.config_.EXPERIMENT_FLAGS. Twice (With the error & Without)

No response

Are any errors or related log-messages shown in the Browser-Console? (F12)

Refused to load safari-web-extension://61B1EEBA-9F99-4234-A87B-4C4493D761DF/js&css/web-accessible/core.js because it does not appear in the script-src directive of the Content Security Policy.

Tested as the only active extension? (incognito mode or another browser users):

No

Expected preferred behavior:

No response

ImprovedTube Version

4.1320.0

Your Settings (From the Extension's ⋮-Hamburger menu > Settings > Backup & reset > Export settings)

No response

Your YouTube-Document

No response

OS / Device:

MacOS 26.5.1 (25F80)

Start with the Safari console error for core.js and the extension settings entries for the missing _locales/*/messages.json resources. Compare the Safari extension package with the working builds on other browsers, then test the App Store installation on Safari. Done means the extension loads on YouTube without the CSP or invalid-resource errors.