The Israeli military has captured Syrian territory, as we read in Axios:

The Israeli military captured territory on the Syrian side of the border in the Golan Heights on Sunday after the Assad regime collapsed, the IDF said in a statement.

…

Israel notified the U.S. in advance about its operation to take control of the buffer zone on the border with Syria and several other key locations on the Syrian side of the border, an Israeli official told me.

Israel told the Biden administration this is a temporary move that will last a few days to a few weeks, until the security situation along the border stabilizes, Israeli and U.S. officials said.

…

Israeli and U.S. officials said that rebel groups attacked at least four UNDOF positions on the Syrian side of the buffer zone in recent days.

The IDF helped the UN Observer Force to repel the attacks.

In recent days, Israel has conveyed messages to several rebel groups in Syria, including HTS, warning them that if they move close to the border in a way that violates the Israeli-Syrian truce agreement, the IDF will take action, two Israeli officials said.

The IDF also took control over the strategic Syrian military outpost on Mount Hermon – the highest point on the border between the countries, Israeli officials said.

This whole situation has immensely escalated, with Israel doing air strikes on Syria:

Israeli officials said the strikes targeted Syrian army air defense systems, artillery batteries and facilities that were connected in the past to Syria’s chemical weapons program.

“We have a responsibility to make sure strategic weapon system doesn’t fall into the wrong hands,” an Israeli official said.

I don’t think Israel is going to be leaving anytime soon.