The use of over-the-counter pyrotechnic products on 31st December 2021 and 1st January 2022 is covered by the rules laid down by a City of Prague Decree.
For more information about locations click here: https://www.praha.eu/jnp/cz/o_meste/magistrat/tiskovy_servis/akce_a_kampane/pyrotechnika/eng/index.html