Jmol does not autoconnect to gtk-3-themes and icon-themes

I’ve uploaded Jmol to the Snap Store but I am getting some inconsistencies with the cursor theme. I am using extensions: [gnome-3-28] in the snapcraft.yaml. If I install the snap from the .snap file everything is fine. But If I install it from the store, there is no auto-connection to gtk-3-themes and icon-themes, whereas sound-themes are still auto-connected. This is not a big deal and only affects the cursor but I am curious what causes it?

Here is the output

$ sudo snap remove jmol
jmol removed
$ sudo snap install jmol_14.6.4+2016.11.05+dfsg1-4build1_amd64.snap --dangerous
$ snap connections jmol
Interface                 Plug                  Slot                             Notes
content[gnome-3-28-1804]  jmol:gnome-3-28-1804  gnome-3-28-1804:gnome-3-28-1804  -
content[gtk-3-themes]     jmol:gtk-3-themes     gtk-common-themes:gtk-3-themes   -
content[icon-themes]      jmol:icon-themes      gtk-common-themes:icon-themes    -
content[sound-themes]     jmol:sound-themes     gtk-common-themes:sound-themes   -
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$ sudo snap remove jmol
jmol removed
$ sudo snap install jmol
jmol 14.6.4+2016.11.05+dfsg1-4build1 from Genadi Naydenov (gantonayde) installed
$ snap connections jmol
Interface                 Plug                  Slot                             Notes
content[gnome-3-28-1804]  jmol:gnome-3-28-1804  gnome-3-28-1804:gnome-3-28-1804  -
content                   jmol:gtk-3-themes     -                                -
content                   jmol:icon-themes      -                                -
content[sound-themes]     jmol:sound-themes     gtk-common-themes:sound-themes   -
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