I am no longer able to display any newly added images or to edit any existing ones (jpg)

Are you referring to display in the editor, or in an article in the front-end of your site?

Hi Ryan,
Thanks for the quick reply. Articles already saved are displaying normally in the front end. The problem is adding new images or editing existing ones.
I have attached a few screen grabs.
Cheers
Mark

Please send me a login - https://www.joomlacontenteditor.net/contact/site-login

It would seem that browser Adblocking extensions I have installed in Firefox - Advlock Plus and UOrigin - are both blocking images in the Adverts folder on your site, but no other! Perhaps the same thing is happening to you?

Hi Ryan,
Top marks for finding that one so quick! I've turned off the ad blocker in Chrome to no effect. I have created a new folder called "Classified" which appears to be a quick workaround. The good news is that I shouldn't need to edit anything in the adverts folder.
Is this glitch down to your update or do I need to look at my hosting provider - it is not unknown for them to "improve" things without them telling you.
Many thanks for your help
Cheers
Mark

Is this glitch down to your update or do I need to look at my hosting provider - it is not unknown for them to "improve" things without them telling you.

Nothing to do with the update, and it definately does look like a browser thing, as I have just been able to re-create the issue on the demo site, with an "Adverts" folder. Renaming the folder to "Averts" fixes the problem. Weird.