I tried one of the links and I got;

Category: Intrusion Prevention Date & Time,Risk,Activity,Status,Recommended Action,IPS Alert Name,Default Action,Action Taken,Attacking Computer,Destination Address,Source Address,Traffic Description

6/6/2019 7:55:36 AM,Medium,An intrusion attempt by deloplen.com was blocked.,Blocked,No Action Required,Malicious Site: Malicious Domain Request 22,No Action Required,No Action Required,"deloplen.com (188.72.215.60, 443)","FRED-PC (10.10.40.14, 56968)",deloplen.com (188.72.215.60),"TCP, https"

Network traffic from deloplen.com matches the signature of a known attack. The attack was resulted from \DEVICE\HARDDISKVOLUME3\PROGRAM FILES\MOZILLA FIREFOX 54\FIREFOX.EXE. To stop being notified for this type of traffic, in the Actions panel, click Stop Notifying Me.

Hi Fred

Thank you so much for taking the time to look at this. I have a follow up question on this matter given your response.

Does this mean that my computer is infected and if it is how do I find and remove problem?

Your help is very much appreciated as I am not sure what to do.

Many thanks

tiger108 said

Does this mean that my computer is infected

I don't know. Further information can be found in this article; https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-caused-malware?cache=no

Run most or all of the listed malware scanners. Each works differently. If one program misses something, another may pick it up.

This could be a problem with OCSP stapling.

Try to disable OCSP Stapling temporarily by toggling this pref to false on the about:config page to see if that has effect.

• security.ssl.enable_ocsp_stapling = false

You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.

• http://kb.mozillazine.org/about:config

It is best to reset this pref via the right-click context menu to true once you are done with accessing an affected website since this is a security feature.

See also:

• https://blog.mozilla.org/security/2013/07/29/ocsp-stapling-in-firefox/