freebsd

If you have to set native resolution on system console (if for example you have to run scfb driver for X), first check resolutions supported by UEFI - escape to loader prompt when booting OS and type:
mode
That should list all textual modes recognized by loader (alternatively you can also try gop list or uga list, but saving gop mode setting using following method won't work (I don't know about uga since my computer doesn't support it)). After this you can set mode you want to use using
mode NUMBER

Things to check:
That you have BusID in your Device section - syntax example BusID "PCI:1:0:0" (you can discover it for example using nvidia-xconfig --query-gpu-info or pciconf -lv). If you have problem with finding modes for monitor you can add Option "ModeDebug" "True" to your Device section in xorg.conf.

First find it with

$ mailq
/var/spool/mqueue (1 request)
-----Q-ID----- --Size-- -----Q-Time----- ------------Sender/Recipient-----------
w0MEs0vA055142 5289 Mon Jan 22 14:54
(Deferred: Operation timed out with some server.)

Total requests: 1

Then delete it using qtool.pl (in sendmail's contrib dir):
./qtool.pl -C /etc/mail/sendmail.cf -d /var/spool/mqueue/w0MEs0vA055142


Run pkg clean. Quite logical, but I keep forgetting command.

Run cert-sync --user /etc/ssl/cert.pem. Omit --user to synchronize for entire system (note that this installs them in /usr/share/.mono rather than /usr/local/share/.mono).

Without this you might be experiencing errors like "Ssl error:1000007d:SSL routines:OPENSSL_internal:CERTIFICATE_VERIFY_FAILED" or similar

Reason for this is application .desktop file missing MimeType specification. For example for me mplayer and thunderbird are not listed as choices for video and mail respectively. To fix this edit application's .desktop file (in /usr/local/share/applications directory, or in ~/.local/share/applications) and run update-desktop-database afterwards (with -v to show its warnings).

To get list of manually installed packages (ie, those not installed as dependencies) use this command:
pkg query -e '%a = 0' %o | sort

In case normal unzip can't handle them properly (I was unable to make it do it properly) use 7 zip instead (package p7zip) - command to use is
7z x path_to_zip

Obviously plugin has to be enabled when building IcedTea. Apparently some systems (like iLo) can't use java web start with OpenJDK. For them applets have to be used but by default they won't open in Firefox - for iLo to work without surprises it is necessary to choose "always activate" for java plugin (Tools > Add-ons > Plugins, then find IcedTea-Web and choose "Always Activate" for it).

TLS 1.2 is not enabled in default version of Mono 4.8.1 port for FreeBSD.