message: Fix flatpak download link: remove dot because it is already in the kLinkFmt
diff: @@ -158,7 +158,7 @@ void Updater::update(bool spontaneous) {
  QString platformArg;
  QString extension = "sh";
  #ifdef FLATPAK
  - extension = ".flatpak";
  + extension = "flatpak";
  platformArg = "";
  // The bundle does not have any version in its filename
  QString link = kLinkFmt.arg(platformArg, "", extension);
  