I have installed the Post Types Order (PTO) plugin with RT-Theme 10. This enabled me to re-order the products on my site manually like I needed to do - so far so good.
However, that plugin has introduced a problem with disappearing left-hand menu on the product category pages used by RT Theme 10:
- When I click on a product category, the left hand menu disappears.
- The products are still listed, so I can click on a product thumbnail and move on to a product page.
- When the product page opens, the menu appears again and works fine.
Disabling the PTO plugin makes the menu work again.
So: there is evidently some sort of conflict between the category pages of this theme, and the PTO plugin.
The Products page in question is located here:
The last 5 sub-menu items under the Products page are Categories (the first one is a static page). And as you can see, clicking on any one of those categories causes the menu to disappear, such as here:
(It also seems like load speed has increased somewhat after installing the PTO plugin, but that's another story.)
FYI: I have tried deactivating ALL other plugins on the site, but that did not resolve the problem.