以前はEMULATEDがデフォだったが
最近はNATIVEがデフォに切り替わった
というところまでは読んだ

このページ見るとNATIVEが書き換えないみたいなんだけど

https://developers.google.com/apps-script/guides/html/restrictions
Rewritten code

In the EMULATED sandbox mode, Caja inspects and substantially rewrites all HTML
and JavaScript before the page loads.
This results in a substantial slowdown in loading times relative to the newer NATIVE mode.
Because code is rewritten, it also becomes difficult to debug.

In NATIVE mode, although comments are still stripped from client-side code,
the code is only rewritten if it contains variables or named functions at the top level,
or if it uses the typeof operator to refer to a variable directly.
The examples below show how to avoid code rewrites in NATIVE mode.

✘Don't — code will be rewritten ✓Do — code will not be rewritten in NATIVE mode
図は逆だよね