How to debug ant-design-mobile code in codepen?

The sample code of

ant-design-mobile can be viewed in codepen, for example, the drop-down refresh component https://codepen.io/pen/?edito.

question:

1, ant-design-mobile the last sentence of the component is ReactDOM.render (< App / >, mountNode); , mountNode is not a specific mount point, it is not supposed to run, but you can see the running effect in codepen, so how does it work?

2, some js code needs to be debugged with console.log () to see the effect, how to do it in codepen? Some code that does not need to refer to third-party resources can be copied to chrome"s console for debugging, but some need to reference react, in the browser console is not easy to do, ask the boss to do something.

Dec.12,2021

mountNode is a dom node that you want to mount. For example, if you have a < div id= "root" > < / div > in your html, mountNode can be replaced by document.getElementById ('root') . In the official example, mountNode is not defined in js, but in the html file, as shown in the following figure

,,Console,,.,ReactDOM,,.
< / p.

MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-7b05b6-126a0.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-7b05b6-126a0.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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