Top: time evolution of the relative m = 2 Fourier amplitude A₂/A₀ in the bar region of the G_LMC, which is defined by [R₀, R₁]=[0.2, 1.0] kpc. Bottom: Bar pattern speed Ω_p determined by the program patternSpeed.py (solid blue) and by means of finite differences (dashed blue). The grey area in top panel corresponds to A₂/A₀ < 0.2, which is the threshold we used to consider whether the G_LMC disc has a bar. The horizontal red line corresponds to the time interval shown in Fig. 1 (from t = −0.10 Gyr to t = 0.12 Gyr). In the bottom panel, we only show the bar pattern speed Ω_p when the G_LMC disc has a bar (A₂/A₀ > 0.2). The vertical dashed purple line corresponds to the G_LMC − G_SMC pericenter.