How to install PHP 7.4.3 on CentOS 8?

Solution 1:

I need to upgrade to PHP 7.4.3 (from 7.4.14)

You understand this is NOT an upgrade, but a downgrade, as 7.4.3 is older than 7.4.14 ?

Using your links.

From MediaWiki

Use PHP 7.4.3 or later instead.

From Roundcubemail

PHP version 5.4.1 or greater (and < 8.0 **)

From PostFixAdmin

Supports PHP7.0+

So 7.4.14 is fine, I don't understand why you think you need exactly 7.4.3, which have lot of security issues (fixed in more recent versions)

Indeed, my repository only have the 2 last minor versions online (so 7.4.13 and 7.4.14 for now), but you can request older, when "really" needed on the forum