message: Open folders using `shell.openItem()`. It should work for everyone.
  closes
diff: @@ -30,13 +30,13 @@ export class AppearanceSettings extends SettingsBase<AppearanceSettingsUi> {
  super(AppearanceSettingsUi, [GENERAL_CONFIG, SYSTEM_CONFIG]);
  this._log = getLogger(APPEARANCE_SETTINGS_TAG, this);
  this._getUi().$on("openUserTerminalThemesDir", () => {
  - shell.showItemInFolder(this._userTerminalThemeDirectory);
  + shell.openItem(this._userTerminalThemeDirectory);
  });
  this._getUi().$on("rescanUserTerminalThemesDir", () => {
  WebIpc.rescanThemes();
  });
  this._getUi().$on("openUserSyntaxThemesDir", () => {
  - shell.showItemInFolder(this._userSyntaxThemeDirectory);
  + shell.openItem(this._userSyntaxThemeDirectory);
  });
  this._getUi().$on("rescanUserSyntaxThemesDir", () => {
  WebIpc.rescanThemes();
  @@ -48,8 +48,8 @@ export class AppearanceSettings extends SettingsBase<AppearanceSettingsUi> {
  const ui = this._getUi();
  const systemConfig = <SystemConfig> config;
  - this._userTerminalThemeDirectory = path.join(systemConfig.userTerminalThemeDirectory, "force_the_directory_open");
  - this._userSyntaxThemeDirectory = path.join(systemConfig.userSyntaxThemeDirectory, "force_the_directory_open");
  + this._userTerminalThemeDirectory = systemConfig.userTerminalThemeDirectory;
  + this._userSyntaxThemeDirectory = systemConfig.userSyntaxThemeDirectory;
  ui.currentTitleBarStyle = systemConfig.titleBarStyle;
  const newFontOptions = [...systemConfig.availableFonts];
  newFontOptions.sort( (a,b) => {
  