Support Forum

I am getting no issues this end. But of course you may have different options set.

Have you tried a temporary switch to one of the WP default themes simply to establish whether your belief that it is the theme is correct?

There almost certainly will come a time when you will have to upgrade so it is best not to let this lie. If I were you I would go back to the theme authors and send them this:

Simple:Press displays it's forum content on a standard WordPress page. This means that it is subject to the same filters and actions as any other WP post or page content. Quite clearly, after the page content is created but before it is sent to the client for display, something is trawling through the page content and converting image file names in 'img' tags to lower case.

As this behaviour began with a recent update to the Jupiter theme, and returns to normal with other themes or when Jupiter is reverted to a previous version there appears to be no other likely conclusion than Jupiter being responsible for the issue.

A quick glance through the Jupiter code suggests many points of content filtering as well as use of the php strtolower() function. 

It is easy to point fingers at other components in the rich and varied world of a WP website but this is a unique and one-off problem that is currently resolved by using a prior version of Jupiter. But we all know that this is not something that can be done longer-term so resolving the cause of the problem is important to this user of your theme and our plugin. We remain willing to do whatever we can to resolve the conflict.

This is not correct. Simple:Press is NOT a 'premium' plugin. It is completely free to download and use.