--- a/browser/modules/ExtensionsUI.jsm
+++ b/browser/modules/ExtensionsUI.jsm
@@ -242,17 +242,18 @@ this.ExtensionsUI = {
     let allUrls = false, wildcards = [], sites = [];
     for (let permission of perms.origins) {
       if (permission == "<all_urls>") {
         allUrls = true;
         break;
       }
       let match = /^[htps*]+:\/\/([^/]+)\//.exec(permission);
       if (!match) {
-        throw new Error("Unparseable host permission");
+        Cu.reportError(`Unparseable host permission ${permission}`);
+        continue;
       }
       if (match[1] == "*") {
         allUrls = true;
       } else if (match[1].startsWith("*.")) {
         wildcards.push(match[1].slice(2));
       } else {
         sites.push(match[1]);
       }