xfce session restart type is "never" for caja
 

Slackware64 Current Multilib with XFCE 4.12 using Caja 1.12.3 etc. from http://slackware.uk/msb/testing/1.12/x86_64/
Up to and including Caja 1.12.2 its XFCE session restart type was "if running", which caused Caja to restart upon a subsequent session start.
With Caja 1.12.3 the session restart type became "never", so Caja no longer restarts upon a subsequent session start.
For as far as I am aware the session restart type cannot be changed.
Any hints would be appreciated.
:D

Click or double-click the "Never" and you are offered the choices of values other than never, this is true under Slackware running Xfce4. Try change the Never to any acceptable values like "Immediately" or "If running".

According to git history there are no changes between 12.2 and 12.3 that are related to your changes
https://github.com/mate-desktop/caja/commits/1.12

@malekmustaq: Aarch! I right-clicked and nothing happened. It never occurred to me to just click. Speaking about discoverability ...

@willysr: Thks for checking.

:D

Ok, I set the session restart type to "if running" and indeed with the next session restart Caja opens. However, the session restart type is now back to "never" and Caja does not open at subsequent session restarts. Probably this is how "never" came about in the first place ...

I gave up and instead copied the caja.desktop file to /etc/xdg/autostart/ and ticked Caja in the Application Autostart list. This "big hammer" works ...
:D