The krunner spellcheck plugin always returns "Could not find a dictionary", although both aspell and hunspell are installed. Tested on Neon (5.11.5) and Debian testing (5.10.5).
*** Bug 388108 has been marked as a duplicate of this bug. ***
Same here: kf5.karchive: bzDecompress returned -5 The dictionary data engine timed out (word: "app" ) The dictionary data engine timed out (word: "appl" ) The dictionary data engine timed out (word: "apple" ) The dictionary data engine timed out (word: "apple" ) Neon user addition, Plasma 5.12
You need to have the sonnet-plugins package installed and the hunspell or aspell language packs aswell as configure the correct language in systemsettings for it to work. I'll create a new bug for spellchecking kcm to list this as hints somehow.
Added bug here for the spellchecking kcm: https://bugs.kde.org/show_bug.cgi?id=398247
This was fixed recently! :)