  The kagome metals $A$V$_3$Sb$_5$ ($A=$ K, Rb, Cs) under ambient pressure
exhibit an unusual charge order, from which superconductivity emerges. In this
work, by applying hydrostatic pressure using a liquid pressure medium and
carrying out electrical resistance measurements for RbV$_3$Sb$_5$, we find the
charge order becomes suppressed under a modest pressure $p_{\rm c}$
($1.4<p_{\rm c}<1.6$ GPa), while the superconducting transition temperature
$T_{\rm c}$ is maximized. $T_{\rm c}$ is then gradually weakened with further
increase of pressure and reaches a minimum around 14.3 GPa, before exhibiting
another maximum around 22.8 GPa, signifying the presence of a second
superconducting dome. Distinct normal state resistance anomalies are found to
be associated with the second superconducting dome, similar to KV$_3$Sb$_5$.
Our findings point to qualitatively similar temperature-pressure phase diagrams
in KV$_3$Sb$_5$ and RbV$_3$Sb$_5$, and suggest a close link between the second
superconducting dome and the high-pressure resistance anomalies.
