Is the word comemoração the same in Brazilian and European Portuguese?

No.

While the spelling and core meaning of "comemoração" are identical in both dialects, there is a difference in typical usage. In Brazilian Portuguese, "comemoração" is used broadly for almost any type of celebration, including casual social gatherings. In Continental Portuguese, the word carries a more formal or official connotation (similar to "commemoration"), and speakers are much more likely to use the word "festa" for casual social events like birthdays or parties. Additionally, the surrounding vocabulary often changes (e.g., bebê in Brazil vs. bebé in Portugal).

Brazilian Portuguese Examples

1. A comemoração do meu aniversário foi ótima. (My birthday celebration was great.)
2. Eles fizeram uma comemoração para o novo bebê. (They had a celebration for the new baby.)
3. A comemoração do gol foi muito barulhenta. (The celebration of the goal was very noisy.)
4. Vamos fazer uma comemoração no restaurante. (We are going to have a celebration at the restaurant.)
5. A comemoração da conquista reuniu todos os amigos. (The celebration of the achievement brought all the friends together.)

Continental Portuguese Examples

1. A minha festa de aniversário foi ótima. (My birthday party was great.)
2. Eles fizeram uma festa para o novo bebé. (They had a party for the new baby.)
3. A comemoração do golo foi muito barulhenta. (The celebration of the goal was very noisy.)
4. Vamos fazer uma festa no restaurante. (We are going to have a party at the restaurant.)
5. A celebração da conquista reuniu todos os amigos. (The celebration of the achievement brought all the friends together.)