There is this endless claim that - somehow - territories from Hungary were transferred to the USSR after WWII, altering the western borders of what is today's Ukraina (spelling its name with an 'e' at the end is some sort of a weird corruption).
This claim is as persistent, as it is false.
The historical truth goes more along these lines:

"In the context of the Yalta and Potsdam conferences, although Ukrainian delegates were not present at the summits, the Allies revised the borders and territories, which were subsequently directly integrated into the Ukrainian SSR.
The main territorial transfer was Carpatho‑Ukraine (Transcarpathia), which was ceded to the USSR by Czechoslovakia.
Below are the specific territories transferred to Ukraine, the countries of their origin, and the underlying claims:
1. Transcarpathia (Carpatho‑Ukraine). Country of origin: Czechoslovakia. Context of transfer: after the end of World War II and the advance of the Red Army, the People’s Committee, organized in Mukachevo, declared the withdrawal of troops from Czechoslovakia and voted in favor of unification with “Soviet Ukraine”.
In June 1945, Czechoslovak President Edvard Beneš officially signed an agreement on the transfer of the territory to the Soviet Union.
Justification: the Soviet Union justified this acquisition on ethnic and historical grounds, claiming that the majority of the Ruthenian and Ukrainian population of the region rightfully belonged to the rest of the Ukrainian people."
After the war, Beneš was trying to resolve the 'national minorities' question in Czechoslovakia (given that it was seen as causing pre-war troubles, in part., Sudeten Germans and Magyars in Slovakia), so this transfer was not perceived as particularly controversial.
No territories from Hungary were transferred to the USSR. You may read here on the other border changes after WWII; including from Poland (Galicia -absolutely nothing to do with Gaul or Spanish Galicia, but deriving from the ancient city of Halič (Галич or Halichina) - and Volhynia; and Romania (Bukovina). Agreements on Poland's western borders are also listed (in Rus., but use a translate function):

https://proza.ru/2026/07/02/844

(Putin himself has confused the matter of some theoretical claims by Hungary, but I think he was just throwing a bit of a bone to Orbán.)