Preview
Preview shows you what is inside a file without leaving tessoa. This page covers where the preview appears, which files can be previewed, and the limits they all share; each kind of file has its own page linked below.
Where the preview appears
Where it lands depends on the view you are using:
| View | Preview location |
|---|---|
| Gallery | The middle of the window, one large image |
| Columns | The rightmost column, once you select a file in the last one |
| Details / Icons | A details panel at the side, toggled from a button in the footer |
The toggle sits at the right end of the footer, just left of the folder-visibility button; its tooltip reads Show details panel / Hide details panel. The button is only there in the details and icons views — columns and gallery come with a preview of their own.
The panel can be re-docked: hover that button and four direction buttons slide up above it, moving the panel to the bottom, top, left, or right. Drag the edge between the panel and the list to resize it; in a pane too small to hold both, the panel is not shown and the list goes back to full width.
What can be previewed
| Type | Coverage | Details |
|---|---|---|
| Images | PNG, JPG, GIF, BMP, WebP, ICO | Image preview |
| Text and code | Plain text, config formats, and hundreds of source extensions | Text and code preview |
| Spreadsheets | .xlsx, .xlsm, .xlsb, .xls, .ods | Spreadsheet preview |
| Turn pages, change the layout, open password-protected ones | PDF preview | |
| Archives | zip, 7z, tar, and every compressed tar | Browsing archives |
For file types not in this table, the preview area shows the file icon and the basics — type, size, date modified — and opening the file itself works as usual.
What every preview has in common
- Previews are read-only. Whatever the type, previewing never touches the file: rotating an image, switching PDF layouts, selecting cells in a spreadsheet all change what is on screen and nothing else.
- Decoding happens in the background. A large file may leave the preview area blank for a moment before the content lands, and the interface stays responsive throughout.
- Going over a limit truncates instead of failing. Text stops at a marker line, spreadsheets show at most 500 rows by 64 columns, and enormous images fall back to an icon — none of it makes tessoa error out or hang.
Previewing file contents needs an activated license. Without one the preview area shows a short message instead of the content, and opening the file itself works as usual. The PDF preview additionally needs the Supporter tier. Check your status under Settings → About → License.