Looking through the post-5763 updates one by one, the first one that 
raises some suspicion in this regard is 5784NoEventSensorProcess-ar, 
dated 6 February 04.

So I just did the following:

*  Updated a 3.7a through #5783.
*  Checked for the bug reported by Boris -- found it did *not* occur.
*  Loaded update 5784.
*  Checked for the bug again -- this time the freeze *did* happen.

This establishes quite firmly where and when the bug arrived ;-)

Cheers,

  -- Scott

At 8:07 PM +0100 3/13/04, Boris Gaertner wrote:
>This bug report is for Squeak 3.7alpha  #5816
>running on Windows 98.
>It does not apply to Squeak 3.7 alpha #5763
>on the same platform.
>
>In an image of Squeak 3.7 with all updates up to #5816,
>when I work in an MVC project, Squeak frequently
>freezes. To see the bug, please try this.
>
>1. Create a MVC project.
>2. Enter the MVC project
>3. Open a browser
>4. Open a workspace
>5. Click on the title bar of the browser to make
>it the active view
>  --> now my Squeak is frozen.
>
>This is a serious bug. Currently I do not know
>the reason of the problem, but the problem
>manifests itself reliably. To give me some help,
>can you please try to verify the bug on your system?
>
>Thank you very much,
>Boris