I think it may have to do with changes in 6.10.0, see the release notes.
"Conditionally invisible DOM node changes
We have properly removed the nodes from the document object model (DOM) when they are conditionally invisible. Previously, when a node was hidden by conditional formatting, we made the node invisible but kept it in place. This had a number of disadvantages. For example, child pseudo-class selectors like
:first-child still targeted the nodes that were hidden, which broke the styling. Another disadvantage was that widgets that were hidden were still checked for validation errors. This meant that a required-but-hidden input field could prevent the page from being saved.
We fixed these issues by actually removing nodes from the document when they are not visible due to conditional formatting. This has the additional benefit that it improves performance for pages that use conditional formatting, as hidden nodes no longer pollute the DOM and slow down the browser. (Ticket 38955)”
Could you give a more elaborate description about what you're trying to achieve? As I'm not sure if I understand you correctly.
Based on your description, I'd say you're trying to execute a microflow which resides on a non-visible element in a page after that element becomes visible, am I correct? If so, you could try refreshing the (main) page object after you've set the visible condition. This should trigger the microflow.
Hmm, only last week I solved an issue with a validation error on a hidden part of the form in Mx7.22.1. That must be a bug then.