Eric, it feels very broken. The fact that is happens for all three last versions makes it even more scary. There is definitely something weird happens to the document and/or machine/fonts/preferences.

Sure, please share the complete package (File > Package). Send it over sharewithai@adobe.com and put the link to this issue in the body of the email (https://illustrator.uservoice.com/forums/601447/suggestions/45020731)

Let's hope that the investigation finds something.

Meanwhile I am thinking — does the dragging the artwork from one tab to another helps? Why add something in a Library, when you just drop it into another document as is. Works for me (but yeah, I'm on Windows).

under the prefs, I have tried pretty much every combination of turning things on and off. same result.

I don't even know what a buffer manager is! so I am going to say no. I am on Mac, maybe that is on the windows side?

it is consistent across reboots, restarts, showing away prefs, reinstalling.

here is the thing about fonts. I am using the same 2 fonts for all of the text, and when I copy and paste it, some of the text remains editable, some it turns to outlines. some of each, but it is always the exact same ones.

I can't make a new file with this artwork, since copy and paste does not work. if I make a copy of the file, delete every single thing other than this design, it still does it.

I started to get this dialog now. then I hit ok and it turns the file into wire mode, and I cannot put it back into preview mode. get the same dialog until I delete the art that was just pasted. so that makes it unusable.

the workaround I have to use is to copy the artwork to a library, then drag out a copy of it anywhere I need and hope that it doesn’t break that file. I have to change a number in every instance of this artwork as part of the design, so this is just a nightmare.

making a new blank document, I make a copy of the library element. then all of the text is editable, but if I copy that element after changing the number, to paste it another part of the layout or design, it is outlines. so I have to either option drag it, or start it over from the library. and if I have to make a 2nd document that goes along with this design, then I have to start from scratch every single time, since I cannot copy paste from one document to another.

and copying that object to the library just to bring it over to another document is the worst solution I can think of from a productivity standpoint. a dozen steps rather than a copy paste.

I have tried going back 3 versions of illustrator to see if any of those worked, all the same.

I can send you a file if it will help, but this just sucks.

Eric, what options are enabled for you in Preferences > Clipboard Handling section?
Does toggling Include SVG Code make a difference?
Do you by any chance use any buffer managers?
Is the behaviour consistent is you launch Ai solo, after a complete reboot?
Does it happen with old documents, or only one particular?
Have you tried using different fonts?

More details needed!

Copying and pasting text turns random parts of it to outlines. if you Option-drag the text, it works fine, keeps all the text in tact. this happens even in the same document, other documents.

Makes working pretty much impossible between documents and just a pain in the same document.