Add link to Firefox 52.9 direct download in WinXP gallery Notes

[merlos]

Currently in within the gallery in the Windows XP item, in the Notes, section there is a reference recommending to install Firefox 52.9.

Due to the age of this operating system, Internet Explorer 6 will NOT work at loading most websites even if internet is working. You should download Firefox 52 ESR, the last version to support Windows XP and use UTM’s directory sharing feature to install it.

The link https://www.mozilla.org/en-US/firefox/52.9.0/system-requirements/ displays some release notes, however in that page there is no link to download the installer and the link to download redirects to current version. It takes a few steps to find the actual installer...

The request is to, in addition to the info link, to add a link to the installer download which could be one of these:

1. https://ftp.mozilla.org/pub/firefox/releases/52.9.0esr/win32/en-US/Firefox%20Setup%2052.9.0esr.exe
2. https://ftp.mozilla.org/pub/firefox/releases/52.9.0esr/win32/en-US/
3. https://ftp.mozilla.org/pub/firefox/releases/52.9.0esr/win32/