If anyone else has accidentally lost blueprints from their library due to the behaviour changes, looks like there may be an automatic backup of blueprint storage for you Have a look for a "blueprint-storage-version-0.18experimental-backup.dat" file.

And 10 seconds into this update and I've already "lost" a blueprint book by deleting from my inventory without realising it was no longer in my library... Goodbye hours of work

Something I find myself doing very frequently is multiplying the output of a decider combinator by -1.

Since the combinator already has output options for 1 and Input Count, it would be a nice to see this expanded to include output options for -1 and Negative Input Count as well.

Just had exactly the same happen to myself as well - I'm, running Windows 10 so issue not isolated to MacOS as post title suggests. Attaching my log files. Note: Using the "Sync Mods With Save" works and the map loads without error, just occurs if you load without the correct mods active. ...

Minor UI bug: Long server names in the browse public server window overlap with the player counts as per attached screenshot.

Note: I am running on a 4K monitor with windows 10 UI scaling at 150% and factorio UI scaling at 200% "Automatic"