In the good old days (pre-v2-apache), my perl scripts (which disable the perl output buffer) would display their output in a web browser as the data processed, but in recent years, nothing shows up until all the data has finished processing. 
Now that Iām a/the server admin, I should be able to do something about that, but Iāve lost many hours attempting to do so, without success. Iāve surmised that it has something to do with DEFLATE and OutputBufferSize, and so I pronged apache2.conf to AllowOverrides just so I could quickly and easily try lots combinations of directives in an .htaccess file, all to no avail.
I did notice the handy gzip OFF in hestiaCPās nginx /edit/server/nginx/ Configure Server: NGINX page, which seemed so promising, but that was not sufficientā¦
WORSE, I think I found a hestiaCP issue on the /list/server/ page:
if I check the box to the left of nginx and then āApply to selectedā ā Restart, then click the arrow, the circle goes round and round, then it SOMETIMES in response loads /list/user/ (!). But after telling hestiaCP to restart nginx, /list/server/ still tells me that nginx has been up and running for days!
if I do a systemctl restart nginx, then /list/server/ shows that it has been freshly restarted.