File & Folder Locations

Paintapp can reach files in several different places: folders on your computer that you have granted access to, its own storage inside the browser, and connected cloud services. Whenever a setting remembers a folder — a Quick Export destination, an OpenColorIO configuration folder — it has to record which of those places the folder is in, not just its name. This page explains the format those settings use, the Select button that fills them in, and how files are addressed when you open one in a browser tab.

See Using Local Files for how folder permissions work and why the browser sometimes asks again.

Where you meet a folder setting

Setting	Where
Destination Folder	Preferences → Quick Export

All of them behave identically: a text box showing the location, and a Select button to pick one.

Settings that point at a single file rather than a folder — the OpenColorIO Configuration file, and file inputs on some filters — work the same way, with a file button that has the same dropdown.

The Select button

Select is a split button. Clicking the main part of the button opens your preferred folder picker straight away. Clicking the small arrow on its right edge opens a menu with four entries:

Menu entry	What it does
Select with Files Browser…	Opens Paintapp's own folder picker, which can reach every place Paintapp knows about — granted folders, app storage and connected cloud services.
Select with Native Picker…	Opens your operating system's folder dialog. This is the only picker that can grant access to a folder Paintapp has never seen before.
Use Files Browser by Default	Makes the main button use Paintapp's picker.
Use Native Picker by Default	Makes the main button use the operating system dialog.

This is the same arrangement as File → Open… and File → Save As…, which have their own split buttons in the File menu. On a file button the first two entries read "Save with…" instead of "Select with…" when the setting is choosing where to write a file.

If you have not chosen a default, Paintapp's own Files Browser is used.

How a location is written

A location is a single line of text that names the storage first, then the path inside it:

local:TestFiles/quickexport
app:mypics
gdrive:Photos/2026

Prefix	Where the folder is
local:	A folder on your computer that you have granted access to
app:	Paintapp's own storage inside the browser
gdrive:	Google Drive
dropbox:	Dropbox
onedrive:	OneDrive

Why the prefix is needed

Without it, a saved folder like TestFiles/quickexport is ambiguous — that could be a folder on your disk or a folder in app storage, and there is no way to tell which one was meant. For deciding where a dialog should open, guessing wrong is merely annoying. For a Quick Export destination it would mean your files being written somewhere you did not choose. The prefix removes the guess.

What the path after the prefix means

For local:, the path is relative to the granted folder, not an absolute path on your disk. The browser never hands Paintapp a real disk path, so a location can only refer to a folder you have granted and a path inside it. If you granted D:\Download\TestFiles, then:

local:TestFiles/quickexport   →   D:\Download\TestFiles\quickexport

For app: and the cloud prefixes the path is relative to the root of that storage.

Two granted folders with the same name — say TestFiles from two different drives — cannot be told apart in a location, and the first one found wins. If you work with same-named folders, grant a level higher up so the names differ.

Typing in the box

The box is editable, and what it shows is exactly what is stored — there is no hidden second form. You can type a location by hand, and you can point at a subfolder that does not exist yet if the feature using it creates folders as needed.

A few rules apply to what you type:

• Text with no prefix still works. Settings saved before prefixes existed have none, and Paintapp falls back to guessing: it first looks for a granted folder with that name, then a cloud service, and otherwise assumes app storage. This is the ambiguity the prefix exists to remove, so re-picking the folder with Select is worth doing once.
• Only the five prefixes above count. Anything else before a colon is treated as ordinary text, not a prefix.
• A pasted Windows path will not resolve. Something like D:\Download\TestFiles is left exactly as typed — in particular the D: is not mistaken for a prefix — but it is not a location Paintapp can follow, because it names a place the browser has not granted. Use Select instead, which grants the folder and fills in the correct local: location.
• app: paths are not case-sensitive. Paintapp's own storage matches folder and file names regardless of capitalization, so app:Presets and app:presets reach the same folder. A local: or cloud path follows whatever the underlying filesystem or service does instead.

Downloading instead of choosing a folder

Quick Export offers two destinations, as a pair of radio buttons: Download, or a Destination Folder. They are alternatives — picking one turns the other off. (Export As is different: it always opens your operating system's save dialog, where you choose the folder and the name each time.)

Download is the default, and it is what a fresh install does before you have configured anything: one click and the file appears in your browser's downloads. It is also the only destination that works in every browser — Firefox has no File System Access support at all, so a destination folder cannot be granted there.

Choose a Destination Folder when you are exporting to the same place repeatedly and would rather the files land there directly than go through the downloads folder.

What happens when you export to a folder

• Missing folders in the path are created.
• An existing file with the same name is overwritten without asking. That is the point of a one-click export — if you want to keep previous versions, use Export As and give each one a name.
• If the folder cannot be reached — most often because its permission has not been granted again this session — the export stops and tells you, rather than failing quietly. Re-grant the folder in the File Browser and export again.
• Cloud destinations are not supported yet. A destination on Google Drive, Dropbox or OneDrive reports that rather than writing.

Where the picker opens

Both pickers try to start at the folder the setting currently points to, rather than at some default location. Paintapp's own picker navigates its folder tree to it and fills in the box at the bottom; the native dialog is asked to start there.

After a browser restart this may not work until you have re-granted the folder. Paintapp deliberately does not ask for permission just to decide where a dialog should open — a permission prompt would consume the click, and the picker would not open at all. So the first time you use Select in a new session the dialog may start somewhere else. Once the folder is granted again, it starts in the right place.

Opening a file in a browser tab

Right-clicking a file in the File Browser offers Open in new browser tab. What appears in the address bar depends on where the file lives.

Files in app storage

These open at a readable address built from the file's own path:

http://localhost:8080/user/mypics/test.jpg

Paintapp's service worker — a small piece of the app the browser keeps running in the background — answers that request out of app storage. The address can be bookmarked and reopened later, and it survives closing the tab. It only works in the same browser on the same machine: nothing is uploaded anywhere, and the address means nothing to anyone else.

On the very first load of the app, before the service worker has started, this falls back to a blob: address. Reload once and it will use the readable form.

Files on your computer or in the cloud

These open as a blob: address — a long opaque string that is not readable and stops working once the tab is closed.

This is a real limit rather than an oversight. The service worker holds no permission to your disk and no cloud sign-in; those live in the Paintapp tab itself. A readable address for such a file would fail the moment it was used the way an address is meant to be used — pasted into a fresh tab, or opened after a restart — which is worse than an address that is obviously temporary.

Files that download instead of displaying

Some files download rather than opening in the tab:

• HTML, SVG and XML always download. This is deliberate. Displaying them would run them as a page belonging to Paintapp itself, which would give a file you merely stored the ability to read your app data and sign-in tokens. Downloading is the safe outcome. Opening such a file inside Paintapp is unaffected — this applies only to viewing it as a web page.
• Files whose type Paintapp cannot determine also download. If a file has no recorded type and an extension the app does not recognize, the browser is told not to guess. Opening it inside Paintapp works normally.