> ## Knowledge Base Index
> Fetch the complete knowledge base index at: https://aide.merci-app.com/sitemap.xml
> Use this file to discover available pages before exploring further.
> Pure-Markdown content can be obtained by appending a '.md' suffix to the content URLs listed in the sitemap (without the trailing slash).

# Why doesn't MerciApp activate in subject line fields?


## Understanding the subject field limitation

Let's clear something up: **MerciApp intentionally never activates in subject line fields**. And this isn't just a MerciApp thing — it applies to *all* browser extensions.

### Why does this restriction exist?

Subject fields (like `input type="email"` or `input type="number"`) use a specific input architecture that prevents any extension from integrating safely and technically. Here's why:
* **Technical architecture:** The input field type simply doesn't support inserting markers or rich content
* **Security risks:** Plugging an extension into these specific fields comes with significant technical risks

## A handy workaround: use Snippets (Expand) 🎯


Correction might not be available in subject fields, but **MerciApp's got you covered with Snippets** (the Expand feature).

### How do Snippets work in subject fields?

Snippets work just fine in subject fields because they don't need complex markers. With them, you can:
* Quickly insert predefined text using keyboard shortcuts
* Speed up your typing across all field types
* Stay productive even where correction isn't available

## Want to go further?

Ready to get the most out of MerciApp?
* 📖 Check out our full guide on [How to create a Snippet](https://aide.merci-app.com/en/article/how-do-i-create-a-snippet-ypy6jq/?bust=1777477036080)
* 💬 Drop us a message via chat for personalized tips on making MerciApp work best for you
* 🚀 Explore all our features available across every field type