Currently you can’t preview pages in Wappler the same way as in the browser.
One of the reason - that the layout file isn’t rendered.
Another reason – page doesn’t get query parameters.
(but maybe it is actually one whole reason behind it, I don’t know)
And most of the inner pages (“details”) use query, for example for id of the record.
Therefore, there is no data in the page when previewed in Wappler with App Connect Mode on.
There is a workaround of course. You can set, that in the local environment would be used specific predefined value instead of the query parameter bind. Or something like that.
But it is not as safe and convenient as possible native solution.
As I shared in similar FR: