Mostly for the records, I've had a very similar, but more severe problem. Since upgrading from 14.04 to 16.04, not only were the indicators (other than a11y) missing, but I couldn't log in anymore. The correct password was reproducibly rejected as incorrect. After the next restart of lightdm, things worked smoothly, until the next logout. I'd reckon that the same cause that kept the indicators from loading kept lightdm from connecting to its source of authentication (PAM?), but that's highly guesswork.
The new 1.18.2-0ubuntu2 so far seems to have fixed that variant of the problem, too. -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to lightdm in Ubuntu. https://bugs.launchpad.net/bugs/1605117 Title: Unity greeter indicators don't show on second launch Status in Light Display Manager: Fix Committed Status in lightdm package in Ubuntu: Fix Committed Status in lightdm source package in Xenial: Fix Committed Bug description: [Impact] Unity Greeter indicators don't show second time greeter started. [Test Case] 1. Log in with greeter 2. Log out Expected result: Unity greeter is shown with all UI elements as in step 1. Observed result: Unity greeter is shown but only one indicator shows (accessibility) [Regression potential] Low. The fix was already present in the Bzr branch (removed some unneeded code that would accidentally close stdin). The fix was not released since it hadn't been shown to be a problem before this report. To manage notifications about this bug go to: https://bugs.launchpad.net/lightdm/+bug/1605117/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp