When something does not work
The most common problems and what you can do about them.
| What you see | Likely cause | What helps |
|---|---|---|
| Empty or white page | The file is incomplete, for example because the code was cut off, or the script has an error. | Ask for the complete file again and test it in the preview first. |
| Everything is tiny | The viewport setting is missing. | Add <meta name="viewport" content="width=device-width, initial-scale=1"> to the <head>. |
| Data is gone after closing | Values were not saved in localStorage, only in memory or in sessionStorage. | Call localStorage.setItem on every change. |
| Tool only works online | It loads scripts, fonts or images from foreign servers. | Build everything into the file or leave it out, then check the tool offline. |
| Microphone or camera does not work | The tool needs the extended permission for that. A database (IndexedDB) no longer needs it. | Switch it on in the tool’s settings, only if you trust it. |
| The file cannot be loaded | It is not an .html file or the tool consists of several files. | Merge everything into a single .html file. |
| A gallery tool does not accept my message | Kind, version or fields do not match the shared format, or a text is too long. Gallery tools ignore anything they do not understand for sure. | Send typ, v: 1, id and text and check the fields of the kind (see “Shared messages”). Use target names in the matching language. |
| Entries arrive twice | The receiver does not remember what it has already taken over. | Give each message an id and store the last 200 ids in the receiver. |
| Timer falls behind after the screen was off | The phone throttles tools in the background. Counted seconds get lost. | Calculate with timestamps: remember the start time and recompute the remaining time on every tick. |
| Sorting by dragging does not work on the phone | Drag and drop does not work with touch on Android. | Add buttons to move entries up and down. |