How to turn off tooltips in taskbar and menu items?

[developer1105]

Is this option available in config files?

[stefonarch]

You mean in lxqt-panel? The answer is no, but I think you could edit your theme and make them invisible. Using kvantum you can set a delay for 9999ms for showing them but this will have overall effect.

[tsujan]

Tooltips are controlled by Qt and, to some extent, by the active widget style.

[developer1105]

It could be like Xfce, in dark themes the tooltips are also dark (white letters over black background).
The theme I am using now has light tooltips, black letters over yellow background, very distracting for a black theme.

[tsujan]

It could be like Xfce

It isn't about XFCE or LXQt but about the style of the toolkit: GTK in XFCE and Qt in LXQt.

[Gnomasz]

Just to be sure: is it one of the standard LXQt themes?

[tsujan]

If a Panel tooltip isn't styled by a CSS (=LXQt theme), it'll be drawn by the active Qt widget style (Fusion, Kvantum, Breeze,...). If it's styled by a CSS completely, the Qt widget style will be overridden. That's true for all Panel widgets.

[stefonarch]

The theme I am using now has light tooltips, black letters over yellow background, very distracting for a black theme.

As said, you could edit the theme, copy it to ~/.local/share/lxqt/themes and edit in lxqt-panel.qss the section (mostly at the beginning):

QToolTip {
    border: 1px solid #2b2b29;
    background: #363532;
    padding: 2px;
    margin: 0px;
    color: #f2f1f0;
}

Panel needs reloading after saving.

[developer1105]

Changing the color solved it. Thanks.