In response to further comments by David G. (thanks for the responses and for keeping me honest!), I tried emacs -Q which starts Emacs without any initialization files (either site-init (site-start.el or user-init - I need to checkor early-init though - I'll do that later and update this update - I need some sleep). But the GTK suggestion is intriguing (although gnome-terminal also uses libgtk-3.0 I built an Emacs without a toolkit at all and seesit behaves as expected wrt to F10 - but there may some option that: the key is visible and I have not been ablecan bind it to find yeta command. I see if I can build Emacsthen found withoutthis section in the GTK documentation: it's about GTK4 and seeI cannot find the equivalent in the GTK3 documentation, but I'm assuming that the behavior is the same in the two versions. I'm no GTK programmer, so I don't know how to turn this behavior off yet, but it seems clear that goesDavid G.) was right when he fingered the GTK interface in Emacs as the culprit.
In response to further comments by David G. (thanks for the responses and for keeping me honest!), I tried emacs -Q which starts Emacs without any initialization files (either site-init or user-init - I need to check early-init though - I'll do that later and update this update - I need some sleep). But the GTK suggestion is intriguing (although gnome-terminal also uses libgtk-3.0 and sees F10 - but there may some option that I have not been able to find yet. I see if I can build Emacs without GTK and see how that goes.)
In response to further comments by David G. (thanks for the responses and for keeping me honest!), I tried emacs -Q which starts Emacs without any initialization files (either site-init (site-start.el or user-init or early-init). But the GTK suggestion is intriguing. I built an Emacs without a toolkit at all and it behaves as expected wrt to F10: the key is visible and I can bind it to a command. I then found this section in the GTK documentation: it's about GTK4 and I cannot find the equivalent in the GTK3 documentation, but I'm assuming that the behavior is the same in the two versions. I'm no GTK programmer, so I don't know how to turn this behavior off yet, but it seems clear that David G. was right when he fingered the GTK interface in Emacs as the culprit.
In response to further comments by David G. (thanks for the responses and for keeping me honest!), I tried emacs -Q which starts Emacs without any initialization files (either site-init or user-init - I need to check early-init though - I'll do that later and update this update - I need some sleep). But the GTK suggestion is intriguing (although gnome-terminal also uses libgtk-3.0 and sees F10 - but there may some option that I have not been able to find yet. I see if I can build Emacs without GTK and see how that goes.)
In response to further comments by David G. (thanks for the responses and for keeping me honest!), I tried emacs -Q which starts Emacs without any initialization files (either site-init or user-init - I need to check early-init though - I'll do that later and update this update - I need some sleep). But the GTK suggestion is intriguing (although gnome-terminal also uses libgtk-3.0 and sees F10 - but there may some option that I have not been able to find yet. I see if I can build Emacs without GTK and see how that goes.)
UPDATE: in response to the comment by David G. below, xev does see F10 (and so do gnome-terminal and xterm as mentioned above, and of course whatever makes the File menu to drop down in the case of Emacs, Firefox and Thunderbird). The problem is not that it is not seen: the problem is that it is grabbed before I want it to be grabbed and I don't know what grabs it. That's what I'm trying to find out in the hope that I can convince that something to keep its hands off my F10 :)
UPDATE: in response to the comment by David G. below, xev does see F10 (and so do gnome-terminal and xterm as mentioned above, and of course whatever makes the File menu to drop down in the case of Emacs, Firefox and Thunderbird). The problem is not that it is not seen: the problem is that it is grabbed before I want it to be grabbed and I don't know what grabs it. That's what I'm trying to find out in the hope that I can convince that something to keep its hands off my F10 :)