This was a fun experiment. I read the dilbert comics using the comic strip widget in Kubuntu. The comics started from 01-01-1994 on the widget while on the website, the first one was on 16-04-1989. Well, I cannot just sit back and miss on the 5 years of comics now, can I??
To change the start date, you will need to modify the start date in ~/.kde/share/apps/plasma/comics/dilbert/contents/code/main.es file.
Open the file in any text editor and search for 1994. The line should be something like -
comic.firstIdentifier = "1994-01-01"
just change it to
comic.firstIdentifier = "1989-04-16"
to get the comics from 1989 onwards. Once you make the change, right click on the widget and click on the "Jump to first strip" option to get the first strip from 1989. Enjoy.