I can't get Canvas Studio to edit a lecture I recorded using a different system.
Answer
The video editing tool is only available for a new Screen Capture made in Canvas Studio, before you click the green "Upload button". Once you click that button, you will be unable to edit the video.
Canvas Studio Editing is not available for mp4 files imported or linked from YouTube. OpenShot, https://www.openshot.org, is an open-source program that we recommend faculty and students use for quick, simple edits: e.g. trimming, clipping and adding a still image.