Please use renderAsync in your browser client instead.
The render function probably changes false to string "false".
This is because it uses the html form submit which doesn't reflect bool types.

Do you use xlsx recipe or the html-to-xlsx recipe?
Also, can you share the logs?

Maybe you get the error for 1mil of rows because of the reached memory limit.
Try to increase the memory limit for the nodejs.

From this blog post...

Set the NODE_OPTIONS environment variable

NODE_OPTIONS=--max-old-space-size=6096

Run jsreport

jsreport start

You can use an asset for it.
https://jsreport.net/learn/assets

{#asset moment.js}
function beforeRender(req, res) {
  moment()....
}

pdfCreatePagesGroup expects parameter and you are calling it with undefined.
It works for you in studio because you have likely different data there compared to the API call.
Make sure you call pdfCreatePagesGroup with param.

Don't know it from the top of my head, but you can easily find it out.
Create simple xlsx in your desktop excel with the boundary you like.
Then save it, rename it to the zip and inspect the xml how is it defined.
Then replicate the same using xlsx helpers.

Thanks. I get timeouts on my desktop as well. The report is not very big, but chrome somehow performs purely for it.
I tried to remove code from your report step by step to find out what is causing chrome to fire.
It seems that the problem is table tag together with page breaks.
Please try to reimplement your code to avoid using table tags and use instead just div or maybe flexbox.

Unfortunately, there is nothing we can do and you need to try the mentioned workaround.

Not sure how much power you get in the end from the azure web app. How long it runs on your desktop? 10s for 5 pages is quite too much.
Check from the logs what is taking the most of the time. It is typically the chrome pdf conversion. Try to remove your styles and add them back step by step to check which one is the bottleneck. Then try to work around it.

You should send the input data in the data prop. Not inside the html. Check the API docs
https://jsreport.net/learn/api

   {
      "template": { "shortid" : "g1PyBkARK"  },
      "data" : { ... }   
   }

What I wrote is still valid.
You start the studio on your own first and prepare sample data.
The users will see the same since then.
You could also create it on the file system by hand, but it is easier to do it through the studio so you don't have to know the exact format.

I don't know that SmarterASP, however, it is quite common that shared environments are blocking chrome.
You can raise a question on their support, but quite likely you will end up with Docker or jsreportonline as you say.