This incident in Springfield, Missouri, involved theft of Harris-Walz yard signs (a longer video is here). Trump signs are being stolen, too (see, e.g., video here); people on both sides are doing it.
It shouldn’t happen. Legally, yard signs are private property, and taking them is a crime. It’s morally wrong, too, because it interferes with others’ rights. Let it be, people. Let others express their opinions. Express yours at the ballot box, and with your own yard signs.