There are still some bugs left in Embedded Python, I reported one more yesterday for a very fresh 2023.3 too

Another issue is that it requires much more time, to implement than I expected, so, I need some more time to finish at least one indexing algorithm.

Or use extra symbol for &js, like @, see example

ClassMethod OnPage() As %Status
{
    &js@<
    if ( a > 1) {
        console.log('test')
    }
    >@
	Quit $$$OK
}

The issue is just in `<` sign in the javascript code, replace it with something else, without <>.