Currently a Report cannot have a DOI in Zotero. This is preposterous. In the real world there are plenty of reports that have DOIs. Persistent identifiers are extremely useful and their mention is highly encouraged by some funding agencies.
You can add a DOI to an item type that doesn't support it by putting "DOI: 10.1234/abc" in the Extra field. Additional fields have been delayed for technical reasons but are coming soon.
(and just to be clear, the DOI entered like that in Extra will already be picked up by citation styles and will be migrated to a proper field once it exists)
Hello, I just came across the same issue today, January 22, 2022. The last comment here is from June 2019. Will the DOI field be added to the Report item type anytime soon?
It will definitely happen, how soon (or what exactly "soon" means) isn't clear, but the workaround above is perfectly workable and also how reports with DOIs are already imported from supported sites.
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Will the DOI field be added to the Report item type anytime soon?