diff --git a/src/lib/gm-xhr-parallel.js b/src/lib/gm-xhr-parallel.js
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+/*
+ * https://github.com/Tampermonkey/tampermonkey/issues/2215
+ *
+ * This script provides a workaround for a Chrome MV3 issue (https://github.com/w3c/webextensions/issues/694)
+ * where extensions can't set/delete headers that are preserved over redirects.
+ *
+ * By setting `redirect: 'manual'` and following redirects manually, this script ensures request redirects work
+ * as intended and requests to different URLs are made in parallel (again).
+ *
+ * Userscript authors should include this as a `@require` when they need to make parallel requests with GM_xmlhttpRequest,
+ * especially if requests might take a long time to complete.
+ *
+ * Including this script will modify the behavior of GM_xmlhttpRequest and GM.xmlHttpRequest in Tampermonkey only.
+ *
+ * Usage:
+ *
+ * Add this to the metadata block of your userscript:
+ *
+ * // @grant     GM_xmlhttpRequest
+ * // @require   https://raw.githubusercontent.com/Tampermonkey/utils/refs/heads/main/requires/gh_2215_make_GM_xhr_more_parallel_again.js
+ *
+**/
+
+/* global GM_info, GM_xmlhttpRequest, GM */
+
+const HAS_GM = typeof GM !== 'undefined';
+const NEW_GM = ((scope, GM) => {
+    // Check if running in Tampermonkey and if version supports redirect control
+    if (typeof GM_info === 'undefined' || GM_info.scriptHandler !== "Tampermonkey" || compareVersions(GM_info.version, "5.3.2") < 0) return;
+
+    // Backup original functions
+    const GM_xmlhttpRequestOrig = GM_xmlhttpRequest;
+    const GM_xmlHttpRequestOrig = GM.xmlHttpRequest;
+
+    function compareVersions(v1, v2) {
+        const parts1 = v1.split('.').map(Number);
+        const parts2 = v2.split('.').map(Number);
+        const length = Math.max(parts1.length, parts2.length);
+
+        for (let i = 0; i < length; i++) {
+            const num1 = parts1[i] || 0;
+            const num2 = parts2[i] || 0;
+
+            if (num1 > num2) return 1;
+            if (num1 < num2) return -1;
+        }
+        return 0;
+    }
+
+    // Wrapper for GM_xmlhttpRequest
+    function GM_xmlhttpRequestWrapper(odetails) {
+        // If redirect is manually set, simply pass odetails to the original function
+        if (odetails.redirect !== undefined) {
+            return GM_xmlhttpRequestOrig(odetails);
+        }
+
+        // Warn if onprogress is used with settings incompatible with fetch mode used in background
+        if (odetails.onprogress || odetails.fetch === false) {
+            console.warn("Fetch mode does not support onprogress in the background.");
+        }
+
+        const {
+            onload,
+            onloadend,
+            onerror,
+            onabort,
+            ontimeout,
+            ...details
+        } = odetails;
+
+        // Set redirect to manual and handle redirects
+        const handleRedirects = (initialDetails) => {
+            const request = GM_xmlhttpRequestOrig({
+                ...initialDetails,
+                redirect: 'manual',
+                onload: function (response) {
+                    if (response.status >= 300 && response.status < 400) {
+                        const m = response.responseHeaders.match(/Location:\s*(\S+)/i);
+                        // Follow redirect manually
+                        const redirectUrl = m && m[1];
+                        if (redirectUrl) {
+                            const absoluteUrl = new URL(redirectUrl, initialDetails.url).href;
+                            handleRedirects({...initialDetails, url: absoluteUrl});
+                            return;
+                        }
+                    }
+
+                    if (onload) onload.call(this, response);
+                    if (onloadend) onloadend.call(this, response);
+                },
+                onerror: function (response) {
+                    if (onerror) onerror.call(this, response);
+                    if (onloadend) onloadend.call(this, response);
+                },
+                onabort: function (response) {
+                    if (onabort) onabort.call(this, response);
+                    if (onloadend) onloadend.call(this, response);
+                },
+                ontimeout: function (response) {
+                    if (ontimeout) ontimeout.call(this, response);
+                    if (onloadend) onloadend.call(this, response);
+                }
+            });
+            return request;
+        };
+
+        return handleRedirects(details);
+    }
+
+    // Wrapper for GM.xmlHttpRequest
+    function GM_xmlHttpRequestWrapper(odetails) {
+        let abort;
+
+        const p = new Promise((resolve, reject) => {
+            const {onload, ontimeout, onerror, ...send} = odetails;
+
+            send.onerror = function (r) {
+                if (onerror) {
+                    resolve(r);
+                    onerror.call(this, r);
+                } else {
+                    reject(r);
+                }
+            };
+            send.ontimeout = function (r) {
+                if (ontimeout) {
+                    // See comment above
+                    resolve(r);
+                    ontimeout.call(this, r);
+                } else {
+                    reject(r);
+                }
+            };
+            send.onload = function (r) {
+                resolve(r);
+                if (onload) onload.call(this, r);
+            };
+
+            const a = GM_xmlhttpRequestWrapper(send).abort;
+            if (abort === true) {
+                a();
+            } else {
+                abort = a;
+            }
+        });
+
+        p.abort = () => {
+            if (typeof abort === 'function') {
+                abort();
+            } else {
+                abort = true;
+            }
+        };
+
+        return p;
+    }
+
+    // Export wrappers
+    GM_xmlhttpRequest = GM_xmlhttpRequestWrapper;
+    scope.GM_xmlhttpRequestOrig = GM_xmlhttpRequestOrig;
+
+    const gopd = Object.getOwnPropertyDescriptor(GM, 'xmlHttpRequest');
+    if (gopd && gopd.configurable === false) {
+        return {
+            __proto__: GM,
+            xmlHttpRequest: GM_xmlHttpRequestWrapper,
+            xmlHttpRequestOrig: GM_xmlHttpRequestOrig
+        };
+    } else {
+        GM.xmlHttpRequest = GM_xmlHttpRequestWrapper;
+        GM.xmlHttpRequestOrig = GM_xmlHttpRequestOrig;
+    }
+})(globalThis, HAS_GM ? GM : {});
+
+if (HAS_GM && NEW_GM) GM = NEW_GM;
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