Checking for CSS filter that doesn't YET exist, but SHOULD in the future?

[dumdedumda]

In (#962 (comment)) @dgtlmoon highlighted the following:

* They add a CSS filter for an element that doesn't yet exist, but SHOULD in the future (like a cinema ticket goes on sale `.on-sale`)

* They want changedetection.io to keep checking and notify them when a change/filter was detected

I've tried pasting a CSS filter which doesn't yet exist (e.g. '.on-sale') -- but should in the future -- in the "CSS/JSONPath/JQ/XPath Filters" box but get the following error "Warning, no filters were found, no change detection ran."

Is there a method to force CD to continue checking until the filter is found? Any tips?

Edit: Ticking "[ ] Ignore status codes (process non-2xx status codes as normal)" still results in the above error (i.e., "warning, no filters were found...".

[ta7tUHIJHx4RwR21]

It's still running and checking even with that error. I have a few that do the same thing until the filter shows up. Once it shows up you'll receive an alert.