### What
When you have bad nesting html in your React code, React wil raise
hydration error since the browser html parser might parse it to sth else
different comparing to server html on client. Previously we're display
only the warning in the error description in dev overlay.
Now we introduced another format of displaying pesudo html that
representing your code, with highlighting the html tag that causes the
error. Since React might gives you the whole component stack of React
tree, so we also introduced a way that can collapse the error.
#### Example
https://github.com/vercel/next.js/assets/4800338/622122d6-4d2e-4c8e-95e8-4864343e478b
### Why
The reason we added this is that even we show the html diff, it could
super large due to React ordering the html on client, so the mismatch
might be a lot. The idea here is similar to what you saw when you passed
down a bad event handler into server component, we displayed a pesudo
html as it could hit your mind faster than just seeing the warning. The
best way is to display the source code, but before we can show the
source, getting component stack display as pseudo html instead of here
could be more helpful.
### After vs Before
<img width="400"
src="https://github.com/vercel/next.js/assets/4800338/714119ad-ff23-46a9-bc5a-5601eb390e71">
<img width="400"
src="https://github.com/vercel/next.js/assets/4800338/575f95fa-889e-4cee-ad19-9c2fea06519a">
Closes NEXT-2621
7525633427