## [1.0.6]
### Changed
- Reduced MAX_CONCURRENT_SCANS from 5 to 2 to lower memory usage and improve stability.
- Reduced MAX_SCANNED_IDS from 500 to 200 for more aggressive cache cleanup.
- Increased scan interval from 5 seconds to 15 seconds (SCAN_INTERVAL=15000ms) to reduce resource consumption.
- Added MAX_MESSAGES_PER_SCAN limit (10 messages) to prevent processing too many messages at once.
- Added MAX_MESSAGE_SIZE limit (5MB) - messages larger than 5MB are now skipped to prevent memory spikes.
- Added GC_IDLE_DELAY (100ms) - idle delay after each message to allow garbage collection.
- Rewrote spamMaster_scanUnreadInbox() with IIFE scope isolation for better memory management.
- Applied memory optimization patterns to onNewMailReceived handler with IIFE scope isolation and explicit cleanup.
- Applied memory optimization patterns to context menu handler with IIFE scope isolation and explicit cleanup.
- Deferred body extraction in message_analyzer.js until immediately before API call to reduce memory footprint.
- Deferred body extraction in context_menu.js until immediately before API call to reduce memory footprint.
- Enhanced migration system to handle version jumps correctly with global upgrade tracking flags (spam_master_upgrade_X.X.X) in background/lib/migrate.js
- Improved IP extraction in background/helpers/constants.js to check x-sender-ip header first (most reliable), then extract IPs from both parentheses and brackets in Received headers for better sender IP detection

### Fixed
- Memory leaks in background.js by adding message size filtering, max messages per scan limit, IIFE scope isolation, explicit null assignments for large objects (parts, headers, body), and 100ms idle delays after each message for garbage collection.
- Memory spikes (up to 60MB) during bulk user actions in context menu by deferring body extraction and nulling payload fields after API calls.
- Excessive memory consumption (430MB/hour potential savings) by deferring body extraction in message analyzer until right before API call.
- Failed IP extraction in some cases by enhancing spamMaster_extractIPsReceived() to prioritize x-sender-ip header and extract from parentheses (IP) format in addition to brackets [IP] format in background/helpers/constants.js
- Migration system now properly handles version jumps (e.g., 1.0.3 → 1.0.6) by tracking completed migrations with persistent flags in browser.storage.local in background/lib/migrate.js

### Added
- Explicit memory cleanup after API calls - payload fields (body, headers, attachments) are now explicitly nulled after use to help garbage collection.
- "Rate us" button in options/options-help.html with correct link to Thunderbird Add-ons page (https://services.addons.thunderbird.net/en-US/thunderbird/addon/spam-master/)
- Quick Instructions help table in options/options-help.html explaining: trusted spam filters, Message Filters respect, spam detection tags (orange with fire icon), and whitelist protection (green tags)
- Global upgrade tracking flags (spam_master_upgrade_X.X.X) to ensure migrations run correctly even when skipping versions in background/lib/migrate.js