hi!
I am working with LRT5 and light room classic 6. I had to convert to drg to allow for classic to work with my cr3 files. Anyway, I completed the work flow up to the visual preview part. I completed visual previews but there is no ability to click on deflicker - it is grayed out. I am unsure why this is the case.
thank you in advance!

Thereight be one or more images without visual previews (check the visual lum column). Close LRT, reopen it and load the sequence again. Activate Visual Previews. Wait if the missing ones are being created. If not, remove them from the sequence.
Once all images have visual previews, visual deflicker can be activated.

thank you!
are the ones without the visual previews the ones missing the visual luminosity (just want to make sure!)

Yes, any image that has a visual preview will also show the value for visual lum.

it worked thank you!

I am running into this same problem. I have no missing visual previews. Every file in my sequence has a Visual Lum value. I have rebuilt the previews and I have quit and restarted LRTimelapse. The "Apply" button on the Visual Deflicker button is greyed out and I cannot apply the deflicker.

Is it possible that deflicker is already applied and the button shows refine option only?