It will save the URL and access date/time with title "UpToDate" - no authors, article title, date published, info that would be required for APA style citations.
When not logged in, the UpToDate page doesn't provide any metadata for the review itself, only for the references cited. I don't have access to the database to see if it provides better metadata when logged in. So, I'm not sure that Zotero can improve its import of this site. @adamsmith or @zuphilip might be able to say more.
In any event, if you right click on the Save to Zotero button and choose the Web Page import option, it will import the page title, and you can manually edit to add the authors and date and move "UpToDate" to the webpage field.
Note that the APA manual has rather bizarre inconsistent rules for UpToDate compared to other items. The format it gives for UpToDate is a mix of the formats used for journal articles (e.g., italicizing "UpToDate" but not the review title) and that used for web pages (including the access date). This is not the format used for other types of reviews (e.g., Cochrane reviews). I suggest you enter the item as done here: https://www.zotero.org/groups/2205533/test_items_library/collections/MR2N872S/search/uptodate/titleCreatorYear/items/BFB24TSL/item-list
This will format it like a journal article and omit the accessed date. This is consistent with the general guidelines for access dates given in the manual (only for items with no clear publication date).
The UpToDate translator used to grab all references on an entry rather than the entry proper. They've made this a lot harder to do, so probably not worth it. I think writing a scraper for the entries themselves instead would be pretty simple (the COVID-19 ones are all open access currently).
Also having this issue! UpToDate pages are not saving as a webpage, and only giving me the option to save the 20-30 references that the UpToDate page itself has in the references section...
Upgrade Storage
https://www.uptodate.com/contents/overview-of-the-management-of-type-1-diabetes-mellitus-in-children-and-adolescents
It will save the URL and access date/time with title "UpToDate" - no authors, article title, date published, info that would be required for APA style citations.
In any event, if you right click on the Save to Zotero button and choose the Web Page import option, it will import the page title, and you can manually edit to add the authors and date and move "UpToDate" to the webpage field.
Note that the APA manual has rather bizarre inconsistent rules for UpToDate compared to other items. The format it gives for UpToDate is a mix of the formats used for journal articles (e.g., italicizing "UpToDate" but not the review title) and that used for web pages (including the access date). This is not the format used for other types of reviews (e.g., Cochrane reviews). I suggest you enter the item as done here: https://www.zotero.org/groups/2205533/test_items_library/collections/MR2N872S/search/uptodate/titleCreatorYear/items/BFB24TSL/item-list
This will format it like a journal article and omit the accessed date. This is consistent with the general guidelines for access dates given in the manual (only for items with no clear publication date).