@Wild9 Sorry it's taken so long for me to get back. COVID hit my family in the middle of getting a new job. I will work to put the Quick Connect plugin back in. Since I build from the pre-built containers I can't control which plugins get included. But since it was originally in I will put it in.
That being said, if there are ever any plugins you want you are always free to go download them from guacamole.apache.org. For example, I'm never going to include the vault or history recording storage plugins but they may be downloaded and the JAR file copied into the proper folder. This can also be done with the Quick Connect plugin until I can get the changes made.