On Mon, Aug 12, 2019 at 6:16 PM Jean Louis <bugs@gnu.support> wrote:
I use:  Editor:      GNU Emacs 27.0.50 (build 3, x86_64-pc-linux-gnu, X toolkit, Xaw3d scroll bars)

        Hyperbole:   7.0.3a
        Sys Type:    x86_64-pc-linux-gnu
        OS Type:     gnu/linux
        Window Sys:  x
        News Reader: Gnus v5.13

Making completion list...

Not sure where that is coming from above.
<(Read)> executes (man-show "grep")

Where is man-show defined.  I don't have it in Emacs 26.  Using the same Emacs version as you but under MacOS.

Invoking man grep in the background
if: Variable binding depth exceeds max-specpdl-sizeUnable to load color "unspecified-bg"
Unable to load color "unspecified-fg"
car: Variable binding depth exceeds max-specpdl-size
next-line: End of buffer

Seems like you have loaded something outside of Hyperbole that has caused an infinite loop, maybe improperly overloading a standard man function.

Try starting with no initializations and then loading Hyperbole manually.

Bob