Prerequisites

• I have checked the Wiki and Discussions and found no answer

• I have searched other issues and found no duplicates

• I want to request a feature or enhancement and not ask a question

The problem

Currently, when users add custom blocklists or allowlists to AdGuard Home, they need to manually:

1. Enter the filter URL
2. Manually type or copy-paste a descriptive name for the filter

This creates friction in the user experience, especially when:

• Adding multiple filters at once
• The filter list already has a descriptive title in its metadata (in comments like ! Title: Filter Name)
• Users might not know what name to give to the filter

Proposed solution

Implement an automatic filter name fetching feature that:

1. Backend: Add a new endpoint /control/filtering/check_url that:

   • Accepts a filter URL via POST request
   • Fetches the content from the URL
   • Parses the filter file to extract the title from metadata comments (e.g., ! Title:, # Title:)
   • Returns the extracted title to the frontend
   • Includes permissive URL validation that doesn't require file extensions (many valid filter lists don't have .txt extensions)

2. Frontend: Enhance the "Add custom filter" form to:

   • Automatically call the new endpoint when a user enters a URL (with debouncing, e.g., 800ms)
   • Auto-populate the "Name" field with the fetched title
   • Allow users to override the auto-fetched name if desired
   • Only auto-fetch if the name field is empty or unchanged from previous auto-fetch
   • Show appropriate loading states and error handling

Benefits

• Improved UX: Reduces manual work when adding filters
• Accuracy: Uses the official filter name from the list maintainer
• Speed: Faster filter configuration, especially for users adding multiple lists
• Accessibility: Makes it easier for less technical users to add custom filters

Technical Considerations

• The auto-fetch should be non-blocking and not prevent users from manually entering names
• Implement appropriate timeout handling for slow or unresponsive URLs
• Consider caching mechanisms to avoid repeated fetches of the same URL
• Ensure the feature works in development mode with appropriate debug logging
• Should respect existing user input (don't override if user has already typed something)

Additional Context

This feature would be similar to how many modern applications auto-populate metadata (like browser extensions that fetch titles from URLs, or music players that fetch track information).

Alternatives considered and additional information

1. Pre-populate a database of known filter lists (but this requires maintenance and doesn't help with custom/private lists)
2. Require users to always manually enter names (current behavior, but suboptimal UX)