Test plan — media preview (PR #357 integration)

This plan exists because the media preview was rebuilt, not extended. The image viewer and the video player were two separate components; they are now one gallery. Everything the old components did has to still work, and the things that were added have to work too.

Two halves, and the first one matters more: a new feature that fails is a disappointment, an old one that stops working is a regression.

• Fixtures — a folder holding at least: 3 photos (one portrait, one landscape, one large — 4000 px or more), 2 videos (one landscape, one portrait), 1 PDF and 1 text file. The portrait video is not optional: it is the file that could not be closed before.
• Where — desktop browser, and a real phone or tablet. The touch half cannot be judged from a desktop with emulation alone.
• Before starting — note the build you are testing.

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Part 1 — What already existed, and must still work

1.1 Opening images

#	Action	Expected
1	Open a photo from the file list	It opens full screen, fitted to the window, not cropped
2	Look at the header	The file name is shown
3	Open a portrait photo	Fitted to height, no distortion
4	Open a 4000 px photo	Displayed whole, no scrollbars

1.2 Browsing between images

#	Action	Expected
5	Press the right arrow key	The next image is shown
6	Press the left arrow key	Back to the previous one
7	Press the arrows at the last item	Wraps to the first — it loops
8	Click the on-screen arrows	Same as the keyboard

1.3 Videos

#	Action	Expected
9	Open a landscape video	It plays automatically, with the native controls
10	Look for the poster	The thumbnail is shown before playback starts
11	Use the video's own controls	Play, pause, seek, volume and full screen all work
12	Press the right arrow while the video has focus	The video seeks — the gallery does not change item
13	Move to another item while a video is playing	The sound stops. Nothing keeps playing in the background
14	Close the preview during playback	The sound stops
15	Open a .mkv, a .webm, a .mov	Each plays, or fails visibly — never silently

1.4 Closing

#	Action	Expected
16	Press Escape	The preview closes
17	Click the close button	The preview closes
18	After closing	The file list is where it was, with the same scroll position

1.5 Downloading

#	Action	Expected
19	Click download on the item you opened	That file is downloaded
20	Move two items along, then download	The file on screen is downloaded, not the one you opened

1.6 Untouched by this work

#	Action	Expected
21	Open a PDF	The PDF viewer opens as before
22	Open a text file	The editor opens as before
23	Open an office document	ONLYOFFICE or Collabora opens as before
24	Open a photo from a shared link	Works, with the share's own permissions

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Part 2 — What is new

2.1 Swiping (touch)

#	Action	Expected
25	Swipe right-to-left across a photo	The next item is shown
26	Swipe left-to-right	The previous item
27	Swipe from a photo to a video and back	The gallery mixes both — this is new
28	Swipe a few pixels and release	Nothing happens. A short movement is not a swipe
29	Swipe vertically	Nothing happens — the page scrolls, the gallery does not move
30	Swipe on a video	The next item, exactly as on a photo

2.2 Zoom (touch)

#	Action	Expected
31	Pinch two fingers apart on a photo	It zooms in, centred
32	Pinch together	It zooms back out, no smaller than fitted
33	Double-tap a photo	It zooms in
34	Double-tap again	Back to fitted, centred
35	Drag with one finger while zoomed	The picture moves under the finger
36	Drag to the edge and keep going	It stops at the edge — the picture never leaves the screen
37	Pinch a video	Nothing happens, and the gallery does not change item

2.3 The rule that makes both work

This is the heart of the change, and it is what #354 complained about: dragging used to move the picture instead of turning the page.

#	Action	Expected
38	At fitted size, drag sideways	The gallery moves to the next item
39	Zoom in, then drag sideways	The picture moves. The gallery stays put
40	While zoomed, tap the on-screen arrow	The next item — the arrows always work
41	Check the item you just arrived at	It is at fitted size, not carrying the previous zoom
42	Zoom back out fully, then drag sideways	The gallery moves again

2.4 Zoom (desktop)

#	Action	Expected
43	Ctrl (or ⌘) and the wheel over a photo	It zooms
44	Wheel without the modifier	Nothing zooms — normal scrolling
45	Trackpad pinch (macOS)	It zooms
46	Double-click a photo	It zooms in, then back out

2.5 The bug from #354

#	Action	Expected
47	On Android, open a portrait video	It is displayed whole
48	Look for the close button	Visible, and reachable
49	Close it	The preview closes without reloading the page

Test 49 is the whole reason the issue was raised: the portrait video could not be closed at all.

2.6 Labels

#	Action	Expected
50	Switch the interface to French, open a photo	The buttons are in French
51	Check with a screen reader, or inspect	The buttons carry a translated label, not English text

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Part 3 — Edge cases worth a minute

#	Action	Expected
52	Open the only photo in a folder	It opens; no arrows, no counter
53	Open a photo in a folder of 500 items	It opens promptly
54	Open a corrupt or truncated image	Fails visibly; the preview can still be closed
55	Rotate the phone while zoomed	Nothing is lost; the picture stays usable
56	Open a photo, close, reopen another	No zoom carried over from the first

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What to report

For anything that fails, note the number, the file involved, the device and browser, and what happened instead. Numbers 12, 13, 20, 39, 41 and 49 are the ones to check first if time is short: each one covers something that was either broken before or is easy to break again.