Gstreamer Version Mismatch

I needed the last GStreamer version (the 1.18.3). The thing is I'm on Ubuntu 18.04, and the default GStreamer version registered in apt is the 1.14.5. So I tried to build the version 1.18.3 directly from the sources.

It didn't work, and eventually I used gst-build for that. Now I'm trying to get the default version for Gstreamer again (the 1.14.5), using apt, but I think the fact that I installed the 1.18 from the sources interferes and the 1.14 doesn't work.

I uninstalled the version 1.18 using the commands :

sudo apt remove libgstreamer1.0 libgstreamer1.0-dev libgstreamer-plugins-good1.0-dev gstreamer1.0-plugins-good libgstreamer-plugins-base1.0-dev gstreamer1.0-plugins-base libgstreamer-plugins-bad1.0-dev gstreamer1.0-plugins-bad gstreamer1.0-tools
sudo apt purge libgstreamer1.0 libgstreamer1.0-dev libgstreamer-plugins-good1.0-dev gstreamer1.0-plugins-good libgstreamer-plugins-base1.0-dev gstreamer1.0-plugins-base libgstreamer-plugins-bad1.0-dev gstreamer1.0-plugins-bad gstreamer1.0-tools

I also deleted the built sources. Then I deleted manually the remaining executables in /usr/local/bin. I reinstalled Gstreamer using the same command, but with install instead of remove. It works, but then when I try :

gst-inspect-1.0 --version

I get the following :

gst-inspect-1.0 version 1.14.5
GStreamer 1.18.3

And when I launch :

gst-inspect-1.0 --gst-version

I get :

GStreamer Core Library version 1.18.3

So I have a mismatch, and when I run gst-inspect-1.0, I get :

Total count: 165 greffons (133 éléments de liste noire not shown), 93 fonctionnalités

It's french, it means that I have 165 plugins, but 133 in the black list, from what I understand. And I read that it's probably caused by the version mismatch.

I tried to see what remained of the install once deleted. So after relaunching the apt remove command, I tried :

locate gst

And too much results to post it due to the characters limit, but a lot of results in the folders:

/usr/lib/aarch64-linux-gnu/
/usr/lib/aarch64-linux-gnu/gstreamer-1.0/
/usr/local/bin/
/usr/local/include/gstreamer-1.0/
/usr/local/lib/aarch64-linux-gnu/
/usr/local/lib/aarch64-linux-gnu/gstreamer-1.0/
/usr/share/locale/mt/LC_MESSAGES/
/var/lib/dpkg/info/

It seems to confirm that the apt remove/purge commands are not enough to completely uninstall the remainings of the 1.18 gstreamer version. But what can I do to fully uninstall it and get a clean 1.14 install again ?