Comment 5 for bug 1755899

Today I retested it with a new HDMI cable, but it still didn't work. However, I again installed an update, after which the monitor did come back alive. I have been unable to reproduce the problem ever since. Perhaps, after all, there were other factors in play, but I have no clue as to the root cause.

The update that *might* have fixed the problem:

Start-Date: 2018-03-15 16:13:21
Commandline: apt upgrade
Requested-By: brecht (1000)
Upgrade: libcurl3:amd64 (7.55.1-1ubuntu2.3, 7.55.1-1ubuntu2.4), grub-common:amd64 (2.02~beta3-4ubuntu7.2, 2.02~beta3-4ubuntu7.3), grub2-common:amd64 (2.02~beta3-4ubuntu7.2, 2.02~beta3-4ubuntu7.3), isc-dhcp-common:amd64 (4.3.5-3ubuntu2.2, 4.3.5-3ubuntu2.3), qml-module-org-kde-solid:amd64 (5.43.0-0ubuntu1~ubuntu17.10~ppa1, 5.43.0-0ubuntu2~ubuntu17.10~ppa1), grub-efi-amd64-bin:amd64 (2.02~beta3-4ubuntu7.2, 2.02~beta3-4ubuntu7.3), firefox-trunk:amd64 (60.0~a1~hg20180311r407525-0ubuntu0.17.10.1~umd1, 61.0~a1~hg20180314r408098-0ubuntu0.17.10.1~umd1), libkf5solid5-data:amd64 (5.43.0-0ubuntu1~ubuntu17.10~ppa1, 5.43.0-0ubuntu2~ubuntu17.10~ppa1), grub-efi-amd64:amd64 (2.02~beta3-4ubuntu7.2, 2.02~beta3-4ubuntu7.3), grub-efi-amd64-signed:amd64 (1.85.2+2.02~beta3-4ubuntu7.2, 1.85.3+2.02~beta3-4ubuntu7.3), libkf5solid5:amd64 (5.43.0-0ubuntu1~ubuntu17.10~ppa1, 5.43.0-0ubuntu2~ubuntu17.10~ppa1), curl:amd64 (7.55.1-1ubuntu2.3, 7.55.1-1ubuntu2.4), isc-dhcp-client:amd64 (4.3.5-3ubuntu2.2, 4.3.5-3ubuntu2.3), libcurl3-gnutls:amd64 (7.55.1-1ubuntu2.3, 7.55.1-1ubuntu2.4)
End-Date: 2018-03-15 16:13:35