Hi Vasileilos, On 18/04/2020 09:32, Vasileios Vlachos via trinity-users wrote: > Gerhard I am able to use only gtk2 components, when I am trying with qt, fpgui or qt5 I am getting various errors. Do I have to install > additional packages? Sorry, but I'm away from Trinity for some time now on a gtk2 desktop (Mint Mate) and can not give good advice. But my package maneger gives me the following packages: lazarus-ide-gtk2 lazarus-ide-qt-1.8 lazarus-ide-qt5 You might have to install those. Furthermore the https://wiki.freepascal.org/fpGUI page explains how ro install the fpGUI components. Hope that helps Gerhard