From: John Stone (
Date: Sat Apr 25 2020 - 22:07:53 CDT

  This is almost certainly related to the grid vs. pack issue,
but beyond that MacOS X has been a challenge for the Tk developers.
This paper is worth reading, as it summarizes a bunch of the recent
challenges that had to be overcome to get Tk working on Catalina as
part of the discussion about how to deal with the new "semantic colors"
associated with MacOS X "light mode", "dark mode", etc themes:

I and the developers of the affected plugins are going to have to revise
their code to correct the mixing of pack and grid managers, which was
always technically illegal in Tk, but was silently tolerated in previous
revs of Tcl/Tk, whether it created hangs/infinite loops, or not.

The "pack vs. grid" issue is described here in several variants
(people calling Tk from either Tcl or Python tkinter, same issues at stake):!topic/comp.lang.tcl/ncxQEhQ81TI

These will take a while to resolve yet since it requires individually
correcting all of the affected plugins (e.g. clonerep etc) one at a time.
Since none of the affected plugin codes were written by me, it's not something
that I can rapidly correct as I'll first have to read and debug other people's
code in the case of plugins that are not being actively maintained by their
original developers. We'll see how it goes.

Re OpenBabel: I'm reticent to package OpenBabel with VMD, I think this is
something people can obtain and install on their system independently
of VMD in general. I had contacted the OpenBabel developers many years ago
and they were not willing to allow VMD to directly link against OpenBabel
code as a plugin (viral GPL licensing issues). I don't think I want to
haggle over the licensing issues personally.


On Sat, Apr 25, 2020 at 03:25:50PM +0200, FX wrote:
> Repost of my 3 April 2020 message, which apparently didn???t go through:
> Hello,
> Someone has reported an issue with the 64-bit build of VMD, which I can???t figure out. I am therefore posting it here for the record, and also asking if anyone knows how to debug the issue.
> In some plugins, combo boxes are displayed OK, but they cannot be interacted with. For example take the ???Clone Representations??? plugin:
> The ???top??? and ???all??? combo boxes cannot be clicked. Yet, the ???Clone??? button works. The following error is displayed in the console:
> ERROR) Creation of window for 'clonerep' failed (cannot use geometry manager grid inside .clonerepgui which already has slaves managed by pack).
> This bug is apparently due to the use of Tcl 8.6, and Jérôme Hénin commented about it ( <>):
> > Indeed, apparently some of the stuff is just not compatible with Tcl/Tk
> > 8.6. It works fine with 8.5.
> The last message I can find about it is in <> so??? what???s the status on this?
> Thanks,
> FX

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