Why does a white rectangle flash on my Dawn theme mobile view?

Hello guys again..

Currently I’m facing a new problem…

I just found that from smartphone appears at the bottom a white rectangle when you scroll down fast. It stay for just 2 sec maximum, then disappear.

It appear just by scrolling down and fast.

Link: https://icraft-e.store

It go under pictures..

So I don’t know if is because of TrustSite

That is the function of mobile, not the issue of the site. You can check on every site. You do not need to scroll fast. Just go to the bottom of every site, scroll down and keep then you can see that blank out of your site

I attached a video, maybe I wasn’t very clear in the earlier explanation.

I have to mention also that I did not have this problem before, I think If I remember correctly, that this appeared after inserting the trusted site gadget.
And if you can check the screen recorder, that white thing appears just by scrolling down fast. I think is a common behavior to scroll down fast nowadays, because everyone is in a rush, no time to scroll slowly. Looks like a glitch or something…

I checked with other devices, and it showed up.
I also checked on other websites, with colored or dark backgrounds, and doesn’t show up any blank rectangles…

I figured out that is related to the Chrome browser. On other browsers doesn’t show up.
Is fixable by any chance..?