Method _updateTitle

modules/core/UrlHashSystem.js:249–290

* _updateTitle * Updates the title of the tab (by setting `document.title`)

()

   * Updates the title of the tab (by setting `document.title`)
   */
  _updateTitle() {
    if (!this._started || this._paused) return;
    if (!this.doUpdateTitle) return;

    const context = this.context;
    const editor = context.systems.editor;
    const graph = editor.staging.graph;
    const l10n = context.systems.l10n;
    const changeCount = editor.difference().summary().size;

    // Currently only support OSM ids
    let selected;
    const selectedIDs = context.selectedIDs().filter(id => graph.hasEntity(id));
    if (selectedIDs.length) {
      const firstLabel = l10n.displayLabel(graph.entity(selectedIDs[0]), graph);
      if (selectedIDs.length > 1) {
        selected = l10n.t('title.labeled_and_more', { labeled: firstLabel, count: selectedIDs.length - 1 });
      } else {
        selected = firstLabel;
      }
    }

    let format;
    if (changeCount && selected) {
      format = 'title.format.changes_context';
    } else if (changeCount && !selected) {
      format = 'title.format.changes';
    } else if (!changeCount && selected) {
      format = 'title.format.context';
    }

    let title;
    if (format) {
      title = l10n.t(format, { changes: changeCount, base: this.titleBase, context: selected });
    } else {
      title = this.titleBase;
    }

    if (document.title !== title) {
      document.title = title;
    }
  }


  /**