In Google Sheets, I use CTRL-H to FIND
ceratin entries. K-Meleon uses it to open
the History dialog.

I went to accel.cfg, found it and put a # in front of that line.
Didn't work.

I know I have the right file, because I also disabled <F2>
and that worked.

? Any help appreciated..

Phil

It's also set in places.kmm
Disable the OnInit line below the accel.

It's better to disable setaccel command itself. OnInit also builds menu.

so or

#_Places_SetAccels{
#setaccel("CTRL H","macros(Places_History())");
#}

either

$OnInit=$OnInit."_Places_BuildMenu;";

In general yes, but the lines inside my places_BuildMenu in 75.1 are disabled anyway, because it's build via menus.cfg, so doesn't matter in this special case.
Considering that the shortcut is also defined double in accels.cfg, it would probably be less confusing for users to disable that one too out-of-box.

OK, I understand this.
Haven't inspected menus.cfg for History

Only noticed that too because both lines inside the buildmenu-module were disabled as comments. The old Scite-Editor for kmm's has very obvious syntax-highlighting for comments