[G4] looking for a answer to a icon issue

[Richard ramsowr]

Of late I'v been see a few e-mails popping up in my
inbox with a unknown icon peppered around the posting!

It looks to be a small blue square with a ? inside of
it...

Also of late I'v been have problems open business PDF
files...

Am I missing a plugin or something?

The other day I did empty my cache and reset Safari
(it was slowing down.

Again I'll express my thanks in advance to those kind
enough to respond

ric