- Undo button appears after deleting pages
- Restores original file with all pages
- Re-renders all grids with restored pages
- Auto-hides after 30 seconds
- Pages tab (delete/rotate/reorder) has inline action buttons, no main Execute
- Download link hidden when switching tabs
- Result section reset on tab switch
- Sortable file list with drag handles in merge panel
- Visual order numbers, file info (pages, size)
- Drag to reorder files before merging
- mergeOrder state synced with file list changes
- Execute uses mergeOrder for merge API call
- After any page operation, result PDF re-uploaded as new working file
- All grids (delete/rotate/reorder) refresh with updated pages
- File list updates with new page count
- Previews regenerated from modified PDF
- Seamless workflow: delete pages → rotate remaining → reorder
- Reorder: drag-drop auto-saves after 800ms, no button needed
- Delete: selected pages fade out + shrink on delete click
- Delete button shows Удаление... state
- Reorder hint shows Сохранение.../Порядок сохранён
- Better drop positioning (left/right of target)
- Fixed JS references to removed deletePages/rotatePages/reorderPages inputs
- Execute function now reads from visual page grid selections
- Fixed reorder URL (/pdf/reorder instead of /pdf/rotate)
- Preview API confirmed working (200, image/png)
- Replace text inputs with visual page grid (thumbnails)
- Click to select pages for delete/rotate
- Drag to reorder pages (visual)
- Thumbnails loaded lazily from /pdf/preview/:id/:page
- Selected pages highlighted with blue border + checkmark
- Grid auto-fills, max-height with scroll
- GET /pdf/preview/:fileId — renders first page as PNG (72 DPI)
- GET /pdf/preview/:fileId/:page — specific page preview
- GET /pdf/thumbnails/:fileId — list of all page preview URLs
- File cards show actual PDF thumbnail instead of icon
- Cached previews (30 min cleanup)
- Fallback to PDF icon if preview fails
- 15 API endpoints for PDF operations (pdf-lib, pdf-parse, Ghostscript)
- Frontend with 8 operation tabs
- Merge multiple PDFs, split by page ranges
- Rotate/delete/reorder pages
- Add watermark text, page numbers
- Compress via Ghostscript (screen/ebook/printer quality)
- PDF to PNG/JPG, Images to PDF
- Password protection, text extraction
- Added to sidebar, dashboard (Utils category), DB
