Sequence of actions:

1. Install the following script:

// ==UserScript==
// @name       	test script
// @grant       GM_addStyle
// @match		*://windhawk.net/*
// ==/UserScript==


(function(){

  GM_addStyle("");

})();

2. Go to https://windhawk.net/

Problem:

With "Alternative page mode in Firefox", the test script has a mystrious syntax error.

Without "Alternative page mode in Firefox", the syntax error disappears.

Environment:

• OS: Windows
• Browser: Firefox 132
• Violentmonkey Version: 2.31