Fireworks Permit
Fort Bend Fireworks Sales and Displays Run Through the Fire Marshal
Selling fireworks or putting on a fireworks show in unincorporated Fort Bend County runs through the Fire Marshal, not the county clerk or the tax office. The Fire Marshal's permit page carries a dedicated fireworks application, and the county fire code gives the office authority to inspect and approve retail stands, indoor sales, and public display shows before they happen.
This is the seller's and operator's side of fireworks, not the customer's. A seasonal roadside stand or a public display carries real fire-code and site-safety questions (clearances, storage, how close the stand sits to the road and other buildings), and the county can inspect before it signs off.
Before you advertise a fireworks sale or book a display in Fort Bend County, pull the Fire Marshal's current application and the county fire-code packet, and start early enough to clear inspection. Also check whether your site is actually inside a city limit, because cities run their own fire rules and may ban retail stands outright.
Source to confirm: Fort Bend County - Fire Marshal Permit Applications