Failed to load module "overlay-scrollbar"

[u14183]

Gtk-Message: 05:47:16.250: Failed to load module "overlay-scrollbar"
Gtk-Message: 05:47:16.265: Failed to load module "unity-gtk-module"
Missing fast-path babl conversion detected, Implementing missing babl fast paths
accelerates GEGL, GIMP and other software using babl, warnings are printed on
first occurance of formats used where a conversion has to be synthesized
programmatically by babl based on format description

*WARNING* missing babl fast path(s): "R'G'B' double" to "CIE Lab double"

(gimp-2.10:2): Gimp-Core-WARNING **: 05:47:17.261: Wrong translation for 'tags-locale:', fix the translation!
babl is using a rather long chain, room exists for optimization here
/app/lib/babl-0.1/double.so 0: R'G'B'A double to RGBA double : 0.000000000000
/app/lib/babl-0.1/CIE.so 0: RGBA double to CIE LCH(ab) double : 0.000000000000
gimp_device_info_set_device: trying to set GdkDevice 'VirtualPS/2 VMware VMMouse' on GimpDeviceInfo which already has a device
*WARNING* missing babl fast path(s): "cairo-ARGB32" to "R'G'B'A u8"

Ref: app/org.gimp.GIMP/x86_64/stable
Kennung: org.gimp.GIMP
Architektur: x86_64
Zweig: stable
Ursprung: flathub
Collection ID: org.flathub.Stable
Date: 2018-09-25 01:21:10 +0000
Subject: Update libwebp to 1.0.0. (4384f116)
Commit: f5dc53f0073d0ff26418eb218cf7d099beeca34fd337d8ef03b4b4b02053453c
Parent: 0e44cece9badbcd339bbe5d7ca381b1cd8f228ff44f5841bcc32046c6d680c24
Ort: /var/lib/flatpak/app/org.gimp.GIMP/x86_64/stable/f5dc53f0073d0ff26418eb218cf7d099beeca34fd337d8ef03b4b4b02053453c
Installierte Größe: 212.6 MB
Laufzeitumgebung: org.gnome.Platform/x86_64/3.28
Sdk: org.gnome.Sdk/x86_64/3.28

Solution for non flatpaked gimp, found by googling, but not tested:

apt-get install --reinstall overlay-scrollbar overlay-scrollbar-gtk2
apt-get install --reinstall unity-gtk-module

[TingPing]

Host modules simply aren't always in Flatpak runtimes and these warnings are safe to ignore.