Why can't I comment on specific words in Portable Text fields?

Based on the documentation, inline commenting on distinct words and sentences within Portable Text is indeed a supported feature in Sanity's Comments system. If you're only able to comment on whole sections and not individual text selections, there are a few likely reasons:

1. Studio Version Issue

You're on version 3.21.1, but inline Portable Text commenting may require a more recent version. The Comments feature has been receiving regular updates throughout its beta period. Try updating to the latest Sanity Studio v3 version:

npm install sanity@latest

2. Plan Requirements

Comments is available on the Growth plan and higher, with a 30-day free trial for new projects. Make sure your project has access to the Comments feature. If you're on a free/Starter plan, you might have limited functionality even during the trial.

3. Portable Text Field Configuration

The inline commenting feature needs to be properly enabled for your Portable Text fields. While the feature should work by default on compatible fields, ensure your Portable Text editor is configured as a standard block type without custom configurations that might interfere with the commenting overlay.

4. Browser/Cache Issues

Sometimes Studio features don't load properly due to cached assets. Try:

• Hard refreshing your browser (Ctrl+Shift+R or Cmd+Shift+R)
• Clearing your browser cache
• Testing in an incognito/private window

5. Field Compatibility

Not all field types support inline commenting. The feature specifically works with:

• Standard Portable Text fields (block content)
• Compatible field types at the field level

If you have heavily customized Portable Text configurations or are using custom components, this might affect inline commenting capabilities.

Troubleshooting Steps:

1. Update to the latest Studio version
2. Verify your project is on Growth plan or has an active trial
3. Test on a fresh, standard Portable Text field without customizations
4. Check the browser console for any errors when attempting to comment
5. Try accessing the Studio from a different browser

Since Comments is still in beta, if none of these resolve your issue, you might be hitting a genuine bug. Consider reaching out to Sanity support or posting in the Sanity Slack community with specific details about your schema configuration and any console errors you're seeing.