color render issues with htop

[jerch]

With Ubuntu 18 LTS htop looks broken:

• no recent xterm.js regression, same issues for older xterm.js versions on Ubuntu 18.04
• no issues with htop on Ubuntu 16
• no issues with other terminals on Ubuntu 18 (tested xterm, gnome-terminal and konsole)

Since other terminals work I wonder whether this is an old bug that went unnoticed and now gets triggered by recent changes in either htop or Ubuntu's terminal settings (changed terminfo?).

Update:
Seems to be related to terminfo, if I change the TERM variable to xterm-256color everything is working. The demo default of xterm-color is limited to the 8 standard colors, still there seem to be issues with these colors (as black is not black, and some chars lost the bold flag).
There is another entry xterm in Ubuntu's terminfo which has the right color commands but is still at 8 colors. Looks like a bug in the terminfo db to me.

[theflyingape]

I can confirm TERM set to xterm-256color, xterm-color, xterm, linux, vt220, vt100 all render properly:

$ rpm -q ncurses
ncurses-6.1-10.20180923.fc30.x86_64
$ rpm -q htop
htop-2.2.0-4.fc30.x86_64
$ cat /etc/fedora-release
Fedora release 30 (Thirty)
$ npm ls xterm
dankdomain@2.1.1 /home/rhurst/src/node/dankdomain
└── xterm@3.14.2

Using TERM=pcansi does cause partial background color issues, but does the same using a regular xterm shell.

[jerch]

Ubuntu 18.04 still ships htop v2.1 which is known to have several rendering glitches (hishamhm/htop#840).