SafetyLit MODS.js

To delete the abstract for selected items:

Open Tools - Developer - Run Javascript, paste the following script:

      for (const item of Zotero.getActiveZoteroPane().getSelectedItems()) {
        item.setField('abstractNote', '')
        await item.saveTx()
      }

Select the items you want to erase the abstract for, then click "run" in the Developer window.

This modifies the items in-place, the effect is immediate and non-reversible!