Yes, that sounds like the thing I’m remembering.

> On Jul 11, 2016, at 7:36 PM, Random832 <random832 at fastmail.com> wrote:
> 
> On Mon, Jul 11, 2016, at 19:04, Ronald Natalie wrote:
>> There might have been a simpler icon editor.   My memory of the early X
>> stuff is pretty hazy.
> 
> "bitmap" has a copyright (MIT) date of 1985. It does appear to be geared
> to icon editing, the manpage says it has trouble with sizes greater than
> 99x99.