I use konqueror and noticed the 'preload instance' option. It greatly improve its launch speed and if you haven't tested it yet, you should. The idea is to port this functionality to any other program (be it a KDE app or not). Among the most heavily used, I think Konsole, Dolphin, Kate/Kwrite would greatly benefit of it. I also chose to write it in the autostart wishlist, since, from what is written on the forum, it looks like the most meaningful place to write about it. Reproducible: Always Steps to Reproduce: Steps to have in the end 1. Add a program to the 'preload' list 2. Launch it and enjoy the very very quick startup Konsole already has a kind of 'preloaded window' but there is only one. Also, opening a new konsole is fast, but the shell can take ages to appear: with a really preloaded window (if these terms make any sense), it should just appear with a prompt ready to recieve some text.
Not sure how Konqueror does it, because it has to be integrated in the kdeinit system somehow, but other applications could indeed benefit from the same feature. I would suggest to report this wish it for each application separately, because it cannot be solved outside of the application.
Related issue https://bugs.kde.org/show_bug.cgi?id=257539
*** This bug has been marked as a duplicate of bug 257539 ***