תקצח דין צו"צ בראש השנה ובו סעיף אחד

The Law of Communal Needs on Rosh Hashanah

1. Although on other Yom Tov days that fall on Shabbos, "Tzidkascha" is not recited at Minchah, on Rosh Hashanah that falls on Shabbos, it is recited. This is because it is a day of judgment, and it is fitting to say "Tziduk HaDin" on a day of judgment. This is the practice in Sefarad. However, there are those who say that even on Rosh Hashanah that falls on Shabbos, it is not recited, because it is written, "Your judgments are like the great deep," and one should not arouse judgment on a day of judgment. Additionally, today is Rosh Chodesh, and "Tzidkascha" is not recited on Rosh Chodesh, as explained in siman 292. According to this reasoning, this is the practice in these countries.