What is your operating system?
Windows 10 pro
What is your Shotcut version (see Help > About Shotcut)?
Can you repeat the problem? If so, what are the steps?
I export a frame to use as a stillframe with text. I open the file, drag it to my timeline, make it the duration I want. I click add filter, rich text, and ShotCut adds a NEW screenshot at the VERY END of my timeline +15 minutes. What the hell is going on here? (Please be specific and use the names as seen in Shotcut, preferably English. Include a screenshot or screen recording if you can. Also, you can attach logs from either View > Application Log or right-click a job and choose View Log.)