For those unfamiliar, Zotero is a “free, easy-to-use tool to help you collect, organize, cite, and share research”. It's very popular in university / academia since it makes it trivial to manage in-text citations and works cited / references sections. There are browser extensions and plugins for popular document processing software (including Word, Google Docs, LibreOffice, OnlyOffice, etc).

It's both open source (AGPLv3), and the most popular choice for that type of software. I recommend it to anyone that I see still doing citations by hand.

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From this update, I am looking forward to the following:

Searches are now much more powerful, with support for nested condition groups and automatic mapping of conditions across levels of the hierarchy. It’s now trivial to, say, search for top-level items with a given author AND (a descendant annotation that is either yellow OR red) [...]

It’s now possible to select multiple rows in the collections pane and view items from across all of those views.

For example, you can now select two collections to quickly see all the items from both of those collections, or select a few saved searches to see the combined results from those searches.

You can now easily edit multiple items at once. Simply select multiple items in the items list, click “Edit Multiple Items…” in the item pane, and then make changes, and the changes will be applied to all selected items. Fields that have multiple values will show “Multiple”, and clicking in the field will show the available values (and “Clear all values”).