Help needed

Es selam aleyküm everybody,

I am a revert for about half a year now. Yesterday, I finally gathered my courage to take part in my First taraweeh prayer at a mosque. I learned about the process etc beforehand, but one thing threw me off: after each fourth rekah, the community chanted something together.

Here is a clip to show what was being chanted.

https://youtube.com/shorts/123xTbYcMPs?is=VpnqoGctJJ515xje

I realized that is partly Allahümme Salli, could someone transliterate the whole thing for me? I can't read Arabic yet and in my Ilmihal books, I couldn't find it.

Thanks in advance!