When I set the "UI Scale" to 1.0 and reload the shopping list can not show any item or results after searching finished.
If I uncheck the "UI Scale" in "System -> Advanced" shopping list is working well.

Fixed in the latest alpha (278)

It is very strange.when I set "UI Scale" to other settings(except 1.0) the shopping list also works well after reloading.I have tested with 3 computers((2k display)) and they all only activating auctionator after deleteing WTF folder.

Can you install https://www.curseforge.com/wow/addons/bugsack and report any errors it gives?

I'm not sure what's happening here, but I use "UI Scale" all the time without an issue. Try only activating auctionator.

Checked, we don't have any code that handles UI scale, it "just works" for every value except for 1.

I have installed bugsack and !BugGrabber.There is no error.
I change uiScale to 0.99 or 0.999 by AdvancedInterfaceOptions and the shopping list still works well.
I change uiScale to 1 by AdvancedInterfaceOptions and there is no item and result in shopping list.
I only create one shopping list and there are 5 items in this list.I print some value from the function RefreshScrollFrame in ScrollList.lua
When the uiscale is 0.99 after I click the name of list:
buttonCount:19
numResults:5
populateCount:5
When the uiscale is 1.0 after I click the name of list:
buttonCount:1
numResults:5
populateCount:1

Update, can replicate the effect. I use ui scale to shrink the UI size, but 1 should work, it doesn't: