Safari isn't showing my frame contents

Chrome for OS X shows our old family news page as it has appeared for about ten years ...

On the right side of the page we see two "frames", each referencing a page which holds Javascript that renders Google Reader output. [1]

Recently, however, Safari shows this ...

The frames are gone. This HTML no longer works:

<IFRAME SRC="google_share.html" FRAMEBORDER=0 HEIGHT=300 WIDTH=185 TITLE="JGF Shared Posts">

I don't know whether this is a new Safari bug, or if it's a side-effect security measure of some sort. It sure is annoying.

[1] The reasons I did this are lost in the mists of time. I first put this page up around 1994. Sometime after 2000 I came up with the current scheme to display output from Bloglines, later I adopted it to Reader. A plain-jane web page on my site holds the Javascript that references Google's servers. The Frames reference the local pages. They're embedded in simple tables so they resize nicely. I'll be very annoyed if I have to change the design because of a Safari bug, less annoyed if there's a genuine security risk.

Update 3/6/11: I received a helpful response on Apple Discussions. Another 10.6 user can see the frames. On the other hand, I tried from the Apple Store and they didn't show up.

Update 3/7/11: The Frames are back again. I haven't updated OS X. I did, however, change my DNS provider from OpenDNS back to my ISP. OTOH, they only showed up now, and I did that yesterday. They've always worked in Chrome. This is truly odd.