When comparing Krunner vs Rofi, the Slant community recommends Rofi for most people. In the question“What are the best Linux app launchers?” Rofi is ranked 1st while Krunner is ranked 8th.
Ranked in these QuestionsQuestion Ranking
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.
As it is written in Qt QtQuick using QML.
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 Can run commands
<code>run: st toxic</code> Runs a tox client in the terminal emulator "st".
<code>run: maim ~/Images/screenshots</code> take a screenshot with "maim" and save it to given location.
Pro Great keybindings
They seem to be emacs based.
Pro Case insensitive
Instead of having to worry about case sensitive characters, you can use caps or lowercase wherever you please without causing any issues.
Pro Clipboard history extension
Greenclip adds clipboard manager functionality: https://github.com/erebe/greenclip
Pro Easily switch windows without mouse
Con Does not have a memory
Other app launchers have a feature where they remember often used searches, so say one searches for "Chrome" often, just by typing the first letter "Chrome will appear first in the results due to it being used so often. Krunner does not have this feature, which means everything needs typed out every time.
Con Issues when Caps Lock is active
When typing with Caps Lock activated, it's impossible to use Backspace. Rofi eventually freezes in this scenario.