There are two important things to note about this sc-QED-TD-DFT procedure: 93 (i) Only a single Fock state was included in the off-diagonal coupling blocks ℏg. However, additional photonic basis states become extremely important at large coupling strengths, 163 which is not included in this sc-QED-TD-DFT method. This procedure can be easily extended to necessarily test the convergence of the polaritonic properties on the basis size of the photonic system. (ii) This work does not inherently rely on the use of the ground state scQED-DFT method discussed previously and can be instead coupled with any molecular ground state as computed by any exchange-correlation functional and further used in the canonical TD-DFT blocks A and B. In this way, the ground state orbitals (i.e., Kohn-Sham basis states) themselves do not directly respond to the presence of the cavity through self-consistent iteration but instead only interact with the cavity through the iterative diagonalization cycles that provide the excited states (i.e., Lanczos/Davidson .