Not sure why it's not working for you.

They suggested a line of code to be put into my .httpaccess file.

It's usually .htaccess as mentioned at https://www.hostinger.com/tutorials/locate-and-create-htaccess, but understood about the password issue.

It might be something like this:

<IfModule mod_headers.c>
    Header set Cache-Control "no-cache, no-store, must-revalidate"
    Header set Pragma "no-cache"
    Header set Expires 0
</IfModule>

that you need to add to your .htaccess file (just while developing if you want). But, if you don't get things exactly right, pages on your site won't load.

But, you really shouldn't have to do any of this and ctrl + F5 should be enough.

However, see https://support.hostinger.com/en/articles/1583501-how-to-clear-cache.

<meta http-equiv="Cache-Control" content="no-cache, no-store, must-revalidate">
<meta http-equiv="Pragma" content="no-cache">
<meta http-equiv="Expires" content="0">

to see if it helps. But, I was talking about doing it as an HTTP response header. Not sure how to do that for LiteSpeed that you're running, but you can search for info if the meta tags don't work.

1. On a cell phone - both Android and iPhone?
2. Via JavaScript code from within the webpage so when it loads it runs?

Cache-Control: no-cache, no-store, must-revalidate

in the response header to the client if you want.

Goto the URL opera://settings/clearBrowserData and clear "cached images and files" for all time.

While on http://www.chasertool.xyz/GMapAddressToLatLng.html, click the badge at the left of the address field (usually a lock, but a triangle in this case), goto "site settings" and choose "reset permissions". Maybe goto just http://chasertool.xyz/ and try the same. You might want to try the same thing with https://www.google.com/.

Does the alert work fine in a private window?