Installed beta update 50345 today, it screwed up my app drawer and edited icons. All of the edited icons on my home screen reverted back to stock. All of the folders in the app drawer lost their names and several of them lost apps. The icons in the app drawer all changed size.
I believe this may be a very specific issue to your device. At least that's my guess. No issues here on my Samsung devices. Icons did change size but there is a setting to resize them in the launcher settings... For me... A non issue. If the icons in the dock only changed, I would assume you don't have it toggled to use the same size icon in your dock as the home screen as well as the app drawer. As for icons themselves changing... Never had that issue. I use a very robust icon pack called Whicons. Never had issues. You may want to check in launcher settings under icons and reapply your icon pack. Unless you are using multiple icon packs at once...which may be the issue being that the update may have reverted to whatever you have set as your default icon. Pack.
I also use whicons (I have a B&W theme). The icons that changed were ones that didn't have a default whicon and I edited to assign an icon. I also use Quick Shortcut Maker to create shortcuts to various settings, those shortcuts all changed to point to "settings". What's most annoying is that folders in drawer view and on the home screen no longer reflect what is actually in the folder.