Previews

The panel, quick look and Details

• The preview panel follows the selection: move down the list and it changes with you. Show or hide it with the Preview button or F11. More › Preview position (the ⋯ button) can put it at the bottom.
• Quick look (Space) opens a large preview over the window. The arrow keys walk the files; Space or Esc closes it.
• Details (the button beside the file’s name, or CtrlI) opens under the header: exact size, folder, owner and permissions, dates, the file’s tags, rating and comment, and what the format records (a song’s album, a photo’s size, a book’s author, an archive’s unpacked size). Click a value to copy it. For a folder, or a file with nothing to preview, Details fills the panel.

Each kind of file has its tools in the bar under the header; in a narrow panel the rarer ones move into ⋯. CtrlF finds text in the preview. A link in a document opens with a click, an address in plain text with Ctrl+click. Previews only read: looking at a file never changes it.

Documents

• PDFs open in a reader: a page at a time or continuous, zoom, find, contents, links, and text you can select and copy. A PDF that numbers its front matter in roman numerals is counted as printed. Skwir carries PDFium; Poppler and MuPDF are optional (Settings › Preview: documents › Document engine).
• Word and OpenDocument text read as text, at once and fitted to the panel: headings, lists, tables, footnotes, links and pictures. Set Text documents to Pages to see them as LibreOffice prints them, or to Pandoc. RTF goes through Pandoc.
• Spreadsheets and presentations are shown as pages, converted by LibreOffice in a sandbox and kept in the cache. On Linux, this requires a working bubblewrap sandbox. Excel workbooks open as tables by default, no LibreOffice needed.

Password-protected PDFs, editing and annotations aren’t supported yet.

Books and comics

EPUB books reflow to the panel’s width; chapters follow one another as you scroll, and a footnote opens right under its reference. Change the text size, let lines use the full width, or count a book in the page numbers of its printed edition. Fixed-layout books (picture books, comics) show their pages as designed. With MuPDF installed, Book engine lays every book out in pages.

Comics (CBZ, CBR, CB7, CBT) open in the reader, a page at a time or as a strip.

Pictures

Common formats open at once, with zoom and fit; SVG stays sharp however far you zoom. HEIC and AVIF photos from phones, JPEG XL, camera RAW, Photoshop and GIMP files are drawn by your desktop’s thumbnailer for them, or by ImageMagick (Settings › Thumbnails › Use ImageMagick, on by default). On Linux, thumbnailers run isolated from your files and the network when a working bubblewrap sandbox is available; otherwise, they can run without isolation. ImageMagick requires the sandbox and does not run without it.

Music and video

One player for both: play, seek, volume, speed (pitch kept), audio and subtitle tracks, and full screen. Songs show their cover in a ring that moves to the music.

Keep playing while you browse is on by default: start a song and carry on, and it plays on in a small player at the foot of the panel, with Fullscreen and a menu for the volume, speed and tracks. The footer and your keyboard’s media keys control it too; Previous and Next walk the folder or the playlist. Playlists (M3U, PLS, XSPF, CUE) list their tracks; nothing is fetched from the internet.

Archives

A zip, tar, 7z or other archive shows what it holds as a tree, with sizes and the unpacked total. Click a file inside and it opens as what it is: a photo to zoom, a PDF in the reader. The header becomes a trail (Field kit.zip › shoreline.jpg); click a step or press Esc to go back. Nothing is extracted to your disk unless you choose Extract Here in the archive’s menu.

An archive inside an archive opens too, one level deep. Encrypted archives need another app for now.

Text, code and data

• Markdown and HTML open in a reading mode, with a switch to the source. Scripts never run and nothing is loaded from the internet. Mermaid diagrams are drawn with the optional skwir-mermaid package.
• Jupyter notebooks read like documents: text cells, code, and what each cell printed or plotted.
• Code is highlighted in over 200 languages, in Skwir’s theme or any of bat’s, yours included (Settings › Reading).
• JSON, YAML and TOML fold section by section; files with comments are shown exactly as written.
• Tables: CSV and TSV, JSON Lines, Excel workbooks and SQLite databases (opened read-only).
• Any file can be viewed as bytes, with a jump to an offset and a search for text or bytes.

Fonts, 3D models, maps and more

• Fonts show a specimen and every character they hold. Find sets your own sample text.
• 3D models (STL, OBJ, glTF, 3MF and more) are drawn in a three-quarter view and measured. Blender, SketchUp, FreeCAD, Rhino and DWG files show the picture stored inside; DXF drawings and G-code are drawn from what they hold.
• Circuit boards: KiCad boards and schematics as KiCad shows them, Gerber and drill files layer by layer.
• Tracks and flight plans (GPX, KML, GeoJSON, FIT and more) appear on a map with their distance, time and climb. The map is drawn offline; a background that downloads tiles is used only if you choose one. Offline maps in PMTiles or MBTiles files show what they hold.
• Emails (.eml) show their headers and message, never fetching remote content, and attachments you can preview.

Supported formats

“—” means nothing else to install.

Optional helpers

The skwir package carries the helpers for PDFs, archives and 3D models; they run apart from the window, so a difficult file never freezes it. The rest is optional. Settings › Plugins says what each preview is waiting for.

On Linux, bubblewrap must be installed and allowed to create user namespaces for sandboxed conversions. If the sandbox cannot start, LibreOffice and ImageMagick conversions are unavailable; Skwir does not retry them without isolation.

Other distributions use similar names (gst-plugins-good, gst-libav on Arch). On Arch, the skwir package already holds the player and the Poppler reader.