xbindkeys double counting keypresses (not distinguishing between press and release)

I have a Logitech g502 Proteus mouse, and want to use the "Back" and "Forward" mouse buttons (typically used with browser).

I verified with xev that the mouse button presses are detected. I installed xbindkeys and using various online references setup .xbindkeysrc to map the mouse buttons (6 and 7) to press a series of keys to emulate the correct behavior.

"xte 'key t'"
     b:6 + Release

"xte 'keydown Alt_L' 'keydown Right' 'keyup Right' 'keyup Alt_L'"
     b:7 + Release

The problem, the remap is executed twice, once on press, and once on release. I thought the "Release" modifier would solve this, but it's still ongoing. I verified this by putting in a dummy remap to the letter 't', holding down the mouse button, and seeing one 't' inserted, followed by another 't' on release when I let go.

I did kill all the xbindkeys processes before testing also. running xbindkeys --verbose --nodaemon shows an unusual behavior, in that a press and release are both recorded when I press a mouse button, despite my not releasing the depressed mouse button. The following looks like I pressed and released the button twice, but it was only once:

starting loop...
Button press !
e.xbutton.button=6
e.xbutton.state=16
Button release !
e.xbutton.button=6
e.xbutton.state=16
"xte 'key t' "
    Release + m:0x0 + b:6   (mouse)
got screen 0 for window 510
Start program with fork+exec call

Button press !
e.xbutton.button=6
e.xbutton.state=16
Button release !
e.xbutton.button=6
e.xbutton.state=16
"xte 'key t' "
    Release + m:0x0 + b:6   (mouse)
got screen 0 for window 510

The xte lines themselves on the command line print only one 't.' Any ideas on how to fix/workaround this?

I use xbindkeys in a similar way on one PC to to workspace switching with the mouse side buttons. Looking at my config I see I have & at the end of my xte config lines which I believe runs xte in the background. Perhaps you need that? I am not at that PC to check what happens if I remove tha & from my config:

        # Mouse button 8 (the "back" side button)
        # Re-map to super+page-down (move to workspace down)
        "xte 'keydown Super_L' 'key Page_Down' 'keyup Super_L' &"
          b:8

        # Mouse button 9 (the "forward" side button)
        # Re-map to super+page-up (move to workspace up)
        "xte 'keydown Super_L' 'key Page_Up' 'keyup Super_L' &"
          b:9

Well it seems like this not an issue with Ubuntu or xbindkeys, but with the xrdp mouse driver. I am using an MS Hyper-V VM running Ubuntu 20.04.2, and I came across the following issue on github where someone reports my problem exactly, a "single click (press+release) of a Logitech MX Vertical mouse of button 6 and 7 (forward/backward buttons) two ButtonPress and ButtonRelease events are sent."

xrdpmouse: ButtonPress/ButtonRelease event sent twice

So it seems like there's no easy fix, which is unfortunate.