When comparing Xfce Whisker Menu vs Krunner, the Slant community recommends Xfce Whisker Menu for most people. In the question“What are the best app launchers for UNIX-like systems?” Xfce Whisker Menu is ranked 6th while Krunner is ranked 8th.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro The most simple and convenient app launcher on my experience
Pro Built into Xfce desktop environment
Pro Opens folders/files also
Just by typing name of file or folder, it will give recommendations
Pro Extensible with plugins
Krunner can be extended with the use of "runners" which are essentially plugins for the app launcher to allow for extra functions.
Pro Fast
As it is written in Qt QtQuick using QML.
Pro Lots of handy features
Such as a fully featured calculator, file opening, browser functions, currency conversion, date/time functions, etc.
Pro Great integration with Plasma, developed by KDE
Pro Can be used to open websites
By just typing an URL into the text box users can have the site open in their default launcher.
Pro I'm able to find open tabs from browsers with KRunner which is very nice
Even supports edge browser.
Cons
Con Will not support file search
Limited to application launch: https://bugzilla.xfce.org/show_bug.cgi?id=11551#c2