Login Page Not Loading Due to CSP Issue in Firefox

I am experiencing an issue when trying to log in at login.mailbox.org using Firefox. The page gets stuck on the loading screen (.fullpage-loader), preventing access to the mailbox.

After inspecting the developer console, I found a Content-Security-Policy (CSP) error, which blocks inline event handlers (script-src-attr). The error message in the console is:

Content-Security-Policy: The page’s settings blocked the execution of an event handler (script-src-attr) because it violates the following directive: “script-src 'self' 'unsafe-inline' 'unsafe-eval' 'nonce-...'”
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