Some applications very slow to start up

I am running Tumbleweed KDE Plasma 5, over the past few months I’ve noticed that some applications like kaffeine and chromium are very slow to start up and I can wait quite a long time before anything actually happens and the gui appears. Also some functions in Dolphin are quite slow to initialise the first time after it starts like the delete items window - the outline appears straight away but the contents only appear after quite a few seconds, subsequent delete actions happen instantly. There do not seem to be any errors reported by any of these applications it is just a very slow process to get things going.

Has anyone else experienced this or have any ideas why it is happening?

Stuart