Hi @kakka0930 thanks for the bug report, and thanks @bmccafferty for the further info and bug replication 
We’ve looked into this and it seems like this is caused by an artefact from the Active View menu which is open when you press the “Print / Save as PDF” button. Without opening this menu, please try exporting using the CMD + P hotkey, hopefully there will be no artefacts in the generated PDF. Let us know how you get on, and we will make sure to patch this in the next update.