Method backspace

src/utils/Cursor.ts:873–878

()

  }

  backspace(): Cursor {
    if (this.isAtStart()) {
      return this
    }
    return this.left().modifyText(this)
  }

  deleteToLineStart(): { cursor: Cursor; killed: string } {
    // If cursor is right after a newline (at start of line), delete just that