(i3-gaps + compton) Solid black borders on almost all apps when set to transparent

I am running Fedora 30 with i3-gaps on my laptop and using compton as a compositor. When I try and set transparent borders in my i3 config, borders on most apps appear as solid black. It affects Nautilus, Firefox, Chrome, Spotify, VirtualBox, etc. The borders on urxvt are transparent, as are other parts of my setup such as polybar and rofi, so compton is not entirely broken. The transparency is set in my i3 config here:

set $bg-color            #ff000050
set $border-color        #ff000050
set $indicator-color     #008cff50
set $inactive-bg-color   #ffffff00
set $text-color          #ababab
set $inactive-text-color #676E7D
set $urgent-bg-color     #E53935
set $ws-focused-bg       #000000

# window colors
#                       border              background         text                 indicator
client.focused          $border-color       $bg-color          $text-color          $indicator-color
client.unfocused        $inactive-bg-color  $inactive-bg-color $inactive-text-color $inactive-bg-color
client.focused_inactive $inactive-bg-color  $inactive-bg-color $inactive-text-color $inactive-bg-color
client.urgent           $urgent-bg-color    $urgent-bg-color   $text-color          $urgent-bg-color

Using the last two digits in the hex to set the alpha value. I also use the line

for_window [class=".*"] border pixel 1

to give the borders with no title bars on i3-gaps. Any ideas on how to fix this? EDIT: My compton config is currently:

detect-client-opacity = true;
shadow-exclude = [
        "class_g = 'Firefox' && argb"
];
frame-opacity = 0.0;