Fireworks in your city may be antifa practicing bomb making
Having just read the thread about fireworks being shot off across the country more than usual and not being able to see the colors/explosion, my best guess is that they are trying to make and testing bombs. They are using the black powder from the firework to make homemade bombs. Further, I would be willing to bet that if this is the case, that they will be trying to use them in strategic locations similar to what the Irish Republican Army does, where they try to hit infrastructure but minimize casualties (for optics reasons). This means that likely they will target high value spots such as upscale malls, white/rich neighborhoods, highways, and any other infrastructure that disproportionately hits white or rich populations. Literally wouldn't surprise me if they start attacking their own fucking colleges.
Link to thread for reference:
https://boards.4chan.org/pol/thread/262921553
God bless.