Fix escaping of \ in character class.

> Rejeté. Ce n'est pas un escape.

D’après mes tests, c’est considéré comme un escape. Doubler le
caractère serait suffisant.

    const url = 'https://example\\.com';
    const urlRegexp1 = /https?:\/\/[-a-zA-Z0-9@:%/._\+~#=?]+[-a-zA-Z0-9@:%/_\+~#=]/g;
    const urlRegexp2 = /https?:\/\/[-a-zA-Z0-9@:%/._\\+~#=?]+[-a-zA-Z0-9@:%/_\\+~#=]/g;
    console.log(url.length); // 20
    console.log(urlRegexp1.exec(url)); // ["https://example"]
    console.log(urlRegexp2.exec(url)); // ["https://example\.com"]

static/sfu.js

@@ -738,7 +738,7 @@ function gotPermissions(perm) {
     displayUsername();
 }
 
-const urlRegexp = /https?:\/\/[-a-zA-Z0-9@:%/._\+~#=?]+[-a-zA-Z0-9@:%/_\+~#=]/g;
+const urlRegexp = /https?:\/\/[-a-zA-Z0-9@:%/._\\+~#=?]+[-a-zA-Z0-9@:%/_\\+~#=]/g;
 
 function formatLine(line) {
     let r = new RegExp(urlRegexp);