Zotero:
Zotero is a reference manager and a free, easy-to-use tool to help you collect, organise, annotate, cite and share research. If your institution has enabled the Zotero integration on the Lean Library dashboard, you’ll be able to start using Zotero on the Lean Library browser extension. If your institution has enabled the Zotero feature for you, you’ll be able to start using Zotero on the extension by enabling it in the Advanced Settings. You can read more here.
Once you have enabled it, you can save articles or notes to your Zotero account.
You can right-click on any webpage (including articles and eBooks) and select “Save to Zotero via LL” to save your citations on Zotero Web Library:

An example of saving notes using Zotero
You can also highlight an important text on any webpage, right-click and select “Save to Zotero via LL” to save you’re the text as a note to your Zotero Web Library:

An example of saving notes using Zotero