[Mobile input focus and out-of-focus issues]
【 wechat end ios keyboard fold up the page blank 】
Achieve the effect of position: sticky
Input.focus () standard explanation address, in which, there is a sentence, “User agents must synchronously run the focusing steps for an element whenever the User moves the focus to a focusable Synchronously execute input.focus() in a touch or click event to focus and call the keyboard.