message: Make clicks on the terminal canvas itself give focus.
diff: @@ -151,6 +151,12 @@ export class TerminalCanvas extends ThemeableElementBase implements AcceptsConfi
  this._handleMouseWheel(ev);
  }, true);
  + this._scrollContainer.addEventListener("mousedown", (ev: MouseEvent): void => {
  + if (ev.target === this._scrollContainer) {
  + this.focus();
  + }
  + });
  +
  this._scrollArea.addEventListener(EVENT_RESIZE, this._handleVirtualScrollableResize.bind(this));
  this._scrollArea.addEventListener(TerminalViewer.EVENT_KEYBOARD_ACTIVITY, () => {
  this._virtualScrollArea.scrollToBottom();
  