@Cold-Egg
Thank you I installed the packages and have no issues so far, but the packages are not actively in use so far, but configuration of corresponding software is done. I removed lsphp84-imap beaucse of your hint.
As I upgraded the server from Bookworm I had to remove some "old" Bookworm and install some "new" TRIXIE packages again, too.
Most probably - as you noted - because version number is lower than the former version on Bookworm.
Now:
apt --installed list | grep lsphp84
lsphp84-apcu/trixie,now 5.1.24-1+trixie amd64 [installed]
lsphp84-common/trixie,now 8.4.11-3+trixie all [installed]
lsphp84-curl/trixie,now 8.4.11-3+trixie amd64 [installed]
lsphp84-igbinary/trixie,now 3.2.16-4+trixie amd64 [installed]
lsphp84-imagick/trixie,now 3.8.0-1+trixie amd64 [installed]
lsphp84-intl/trixie,now 8.4.11-3+trixie amd64 [installed]
lsphp84-memcached/trixie,now 3.3.0-2+trixie amd64 [installed]
lsphp84-msgpack/trixie,now 3.0.0-1+trixie amd64 [installed]
lsphp84-mysql/trixie,now 8.4.11-3+trixie amd64 [installed]
lsphp84-opcache/trixie,now 8.4.11-3+trixie amd64 [installed]
lsphp84-redis/trixie,now 6.2.0-2+trixie amd64 [installed]
lsphp84/trixie,now 8.4.11-3+trixie amd64 [installed]