message: rewrite group permalinks in <a hrefs> also
diff: @@ -216,10 +216,16 @@ const sanitizeHtmlParams = {
  m = attribs.href.match(linkifyMatrix.MATRIXTO_URL_PATTERN);
  if (m) {
  const entity = m[1];
  - if (entity[0] === '@') {
  + switch (entity[0]) {
  + case '@':
  attribs.href = '#/user/' + entity;
  - } else if (entity[0] === '#' || entity[0] === '!') {
  + break;
  + case '+':
  + attribs.href = '#/group/' + entity;
  + break;
  + case '#': case '!':
  attribs.href = '#/room/' + entity;
  + break;
  }
  delete attribs.target;
  }
  