docs(linux): add information about mesa

docs/source/troubleshooting/linux.rst

@@ -1,6 +1,28 @@
 Linux
 =====
 
+Hardware Encoding fails
+-----------------------
+Due to legal concerns, Mesa has disabled hardware decoding and encoding by default.
+
+.. code-block:: text
+
+   Error: Could not open codec [h264_vaapi]: Function not implemented
+
+If you see the above error in the Sunshine logs, compiling `Mesa`
+manually, may be required. See the official Mesa3D `Compiling and Installing <https://docs.mesa3d.org/install.html>`_
+documentation for instructions.
+
+.. Important:: You must re-enable the disabled encoders. You can do so, by passing the following argument to the build
+   system. You may also want to enable decoders, however that is not required for Sunshine and is not covered here.
+
+   .. code-block:: bash
+
+      -Dvideo-codecs=h264enc,h265enc
+
+.. Note:: Other build options are listed in the
+   `meson options <https://gitlab.freedesktop.org/mesa/mesa/-/blob/main/meson_options.txt>`_ file.
+
 KMS Streaming fails
 -------------------
 If screencasting fails with KMS, you may need to run the following to force unprivileged screencasting.