Photos crashes every time I manually type in keywords in "Information" box

OT and léonie - thanks to you both! As far as I can tell, my problem is fixed. What I believe started out as currupted keywords or Photos library file is now working, thanks to iCloud and your advice. I was able to create a new Photos library file by holding down the <option> key when launching Photos, and then in Photos/Preferences/General I selected "Use as System Photo Library" to make this new library the main library. Then in System Preferences, I selected "Internet Accounts/iCloud" and made sure that Photos was checked. This then began the process of downloading all my photos from the cloud, where they had been previously syncing with all my devices. It appears that this "fresh" download has all my photos, keywords, faces and places intact so far, and does not have the corrupted keywords. I can now assign keywords by typing them into the correct field in the Information dialog box, and the program does not crash anymore. Thanks for your patience and advice! I am once again back up and running!

Thanks for your time! All my keywords are engllish charactors and words only, and no punctuation nor special characters. I was renaming a keyword in the "Manage my Keywords" dialog box, and it didn't the change. So I attempted to rename it several times. I notied the problem started shortly after this. Again, I have been using Photos since it came out, and the keywords for even longer. I've tried all the usual methods to correct errors, such as quiting and restarting the Photos app, restarting and shutting dow the computer. If anyone can answer my question about rebuilding the Photos database, and what if any effect that has on existing keywords, etc. that would be very helpful. Thanks!

OT - thanks for the recommendations! I started by testing a new library and importing 20 photos. I was able to create and use Keywords with no issues. In regards to your questdion on whether I have my photos backed up in iCloud - yes, I do. All my devices sync through iCloud. How does this impact my ability to repair the library? Should I not try this? I've invested years of time adding keywords and tags and places, etc. to all my photos, and am very worried about creating a problem via rebuild that propogates to all my devices. Does rebuilding the photos library run the risk of losing all this work? Thanks again for your expertise!

OT - one more update. I created a second user account per your suggestion. Of course, Photos started downloading all 76K photos from the cloud. But after several thousand were downloaded, I paused it and tried adding Keywords. It appeared to work with no issues. So it may be either the user account or the number of photos (?). Open to more suggestions. Thanks!

Final insight for now. It appears that in my list of Keywords I have a blank keyword, with no characters, at the top of my list. I tried to delete the keyword, but this automatically crashed my Photos app every time. I tried to add a shortcut, which I can do, but in doing so I have now somehow created 3 more blank keywords. So now I have 4 blank keywords that I cannot apply to a photo (clicking on the button does nothing), and that I cannot delete. So, I can apply all other keywords using the shortcut I have assigned them, oy by selecting a photo and adding the keyword via the keyword dialog box (where you click on the leyword you want to add manually). I just can just no longer manually type in a keyword in the picture Information dialog box, which is where I normally do this.

Thank you very much. I will continue to let the photos on my new account download. Since this is a "new" library downloaded from the cloud onto my new user account, how then do I get it back into my old user account?

Undfortunately, I cannot rename them. When I try, it allows me to type in a bew name, but when I hit <return> to accept the changes, it just creates another blank keyword. Now I have 5 blank keywords, and every time I try and delete one of them Photos immediately crashes.

UPDATE: Now Photos crashes if I even try to select "Keyword" as smart album condition (e.g. "Edit Smart Album" and choose "Keyword" from the condition drop down menu. Boom! Crash every time.