  We examine archival XMM-Newton data on the extremely variable narrow-line
Seyfert 1 (NLS1) active galactic nucleus (AGN) 1H 0707-495. We construct
fractional excess variance (Fvar) spectra for each epoch, including the recent
2019 observation taken simultaneously with eROSITA. We explore both intrinsic
and environmental absorption origins for the variability in different epochs,
and examine the effect of the photoionised emission lines from outflowing gas.
In particular, we show that the unusual soft variability first detected by
eROSITA in 2019 is due to a combination of an obscuration event and strong
suppression of the variance at 1 keV by photoionised emission, which makes the
variance below 1 keV appear more extreme. We also examine the variability on
long timescales, between observations, and find that it is well described by a
combination of intrinsic variability and absorption variability. We suggest
that the typical extreme high frequency variability which 1H 0707-495 is known
for is intrinsic to the source, but the large amplitude, low frequency
variability that causes prolonged low-flux intervals is likely dominated by
variable low-ionisation, low velocity absorption.
