  Utilizing NICER observations, we present an analysis of the soft X-ray
re-brightening event of GRS 1915+105 observed in 2021. During this event, we
observed the emergence of a stable, long-lasting low-frequency quasi-periodic
oscillation (LFQPO) with frequencies ranging from 0.17 to 0.21 Hz. Through a
careful spectral analysis, we demonstrate that a low-temperature Compton-thick
gas model well characterizes the emitted radiation. By examining the spectrum
and identifying numerous absorption lines, we discerned a transition in the
wind properties. This transition was marked by a shift from a state
characterized by low speed, high column density, and high ionization degree to
one featuring still low speed but low column density and ionization degree.
Intriguingly, the presence or absence of the QPO signal is perfectly correlated
with these distinct wind characteristics. The low-speed wind observed could be
indicative of a 'failed wind', while the observed shift implies a transition
from a magnetically to a thermally driven wind. Notably, this QPO signal
exclusively manifested itself during the magnetically driven phase, suggesting
the possibility of a novel perturbation associated with magnetic effects.
