Anyone got Compiz to work? Because I failed, like I did in UM 14.04!
I installed SPM and then Compiz, including all the items cited here by @Wimpy in his 19.10 release info
If you love Compiz, it can be installed by opening a terminal and running the following command:
sudo apt install compiz compiz-core compiz-mate compiz-plugins compiz-plugins-default
Only having one window manager to target means we can promptly deliver new features and minimise development effort.
plus I installed Compiz Config Manager.
And then used MATE Tweak to enable. Result was that I lost all window decoration, including min/max/close. And the Main Menu and all of it's sub-menus had a ~6px black surround. I could find no obvious way to address either ...
Worse, when I used MATE Tweak to reset the Windows manager to Marco (Adaptive) the window decoration and controls came back, but the Main Menus are all moved down and right by those ~6px. You can see it happen when you first go into each menu (I use Traditional layout): the menu displays with the same wide black borders and then those borders instantly turn transparent (I'm testing on a slow DuoCore) but their width does not change. That clears the black borders but doesn't reposition the sub-menu back up and left.
I believe we have 2 issues here, big one first:
Lack of critical Compiz support
Happy to have to install Compiz manually. But it needs to be workable/usable after. In 15.04 IIRC @wimpy added some additional configuration settings to make Compiz work correctly (see here), over and above the compiz-mate CCM option. I believe those have to still be present in a base UM 20.04 insatll, or have some way of installing them via SPM. As it stands Compiz in 20.04 is as bad as it was in the original Ubuntu MATE beta release!
Dependency in Marco menu CSS
The Marco menu CSS seems to assume some default state of the menu's border width which will not be true if Compiz was the prior WM. A reboot without Compiz installed seems to clear this up, and the menus display correctly. But there is an underlying setting issue with the menu border width in Marco CSS. Or, compiz-mate compatibility needs some further additions to bring it inline with Marco in 20.04.
Happy to file either or both of these as bugs if thought appropriate, but not sure who to report them to.
Also happy to test further by copying files over from my 18.04 system - if someone will direct as to which.
[ Also see my message #39 above as to how this can impact users doing and upgrade from 18.04 used with Compiz - they will also lose windows decoration on first boot post upgrade I believe. ]