I am using different colors for different tasks and I would like to add a legend somewhere on the chart, so when I export the chart to PDF and send it to someone outside the organization, they will understand what the colors signify.
Is there a possibility to add a legend to the chart? Or maybe is there a way to input a text message below or above the chart or any other possible workaround?
No such option, sorry.
As a workaround, you may try using fake colored task bars and task names as a kind of legend (see the screenshot). You will need to show the task names for all tasks though.