disappearing icons

The past week or so, I've been dealing with icons disappearing in some website (empty icon next to Spam and Deleted folders in Yahoo mail and message and couch icons in couchsurfing website. But the functions are intact(when I click on the site of missing icon, its function is carried out.

Accidentally, I found out that to make the missing icons re-appear is simply to delete browsing history and refresh the website window.

What causes this disappearing act and why Browser history deletion corrects it?

Hi Andrew...I do ccleaner daily before shutting down. Indeed I was suspecting some default setting in Ccleaner or Internet Option app under Website Data Settings that I might have tweaked to a non-default number or option.

I've been toggling the check box of cookies in both Windows and Application panels to checked and unchecked (Ccleaner)and it did not seem to make any difference. In Internet Option app, most options are default setting including check box(which is checked) to Allow website caches and databases but the space allotted to them set at 10 MB for notifying me if exceeded, might not be default setting. Very possibly I might have tweaked it to 10 MB. Now I wonder if I should increase or decrease that 10 setting.

Can you check yours and tell me your allowed setting for notifying you if exceeded

Everyday, the moment I notice icons are missing, I do History browser deletion with these settings and then refresh the website and icons reappear.

I have to wait for the icons to disappear and then I will log on to Yahoo mail with FF. See what happens.

Aah...while the icons are missing in Yahoo mail with IE 11 they are NOT missing with FF. So indeed it's IE issue again.

"Website data settings I always use Everytime I visit the webpage instead of automatic"

I am very sure my setting on this has always been Automatic. But I'll try Everytime I visit the webpage and see what happens.