I checked this in 24. The previous bug Barry mentioned has been solved (almost). The noticeable change in font size has been reduced to something you almost can't notice, but only when zooming in before pasting text. The same behavior is present with labels (original font size 3,000 changes to 2,998 or 2,999):
Archicad 4.55 - 25 | HP Z840 | 2× E5-2643 v4 | 64 GB RAM | Nvidia Quadro M5000 @ Windows 10 Pro x64
Using AC25 4013 version. Sorry but not installing updates if its not life/death question because recent updates AC25 updates just damages projects (gone dimensions in plan/section views other fun stuff). Which build version do you use ?
GRAPHISOFT BIM Manager Training Week attendee ArchiCAD v9 - v25 INT / NOR i5-12600K @ 5.0Ghz, 32GB ram, GeForce GTX 1060 (6GB) NVMe SSD - Read - 3 GB/s, Write - 2GB/s, Windows 11 ArchiCAD Discord channel: https://discord.gg/VcXcNChkKe
Thank you very much for sharing the problem and I am very sorry to hear about it!
In the past, we had the defect DEF-1315, which affected text size if you copy the text then zoom in/out. Our developer implemented a fix for this problem, which worked perfectly on macOS, but it resulted in a new defect, DEF-3928 on Windows.
Due to a problem with Richtext Editor, the text size changes very slightly even if you don't zoom in/out. We are aware of the seriousness of the issue, however, fixing this bug would require a big resource from development, as it lies deep within the code.
I am very sorry for the inconvenience, and thank you very much for your understanding! Please let me know if you have any further questions!