By using XSL Transforms, a malicious webserver could have served a user an XSL document that would continue to execute JavaScript (within the bounds of the same-origin policy) even after the tab was closed. This vulnerability affects Firefox < 97.
[
{
"vendor": "Mozilla",
"product": "Firefox",
"versions": [
{
"version": "unspecified",
"lessThan": "97",
"status": "affected",
"versionType": "custom"
}
]
}
]