Set it up after installing

The app works the moment it opens, so none of this is required. It is a short checklist of the choices that are worth a minute on the first day, in the order that is most useful. Everything here is in Settings: press Ctrl, (on a Mac, Cmd,) or use Menu, then Settings…. Changes apply as you make them, with nothing to confirm.

1. Check which renderer you have

The viewer draws with WebGPU when your browser and graphics card support it, and with WebGL2 when they do not. Both give the same picture. WebGPU is faster on heavy models.

1. Open Settings, then About. The details list the renderer, your browser and the size of your screen.
2. Open Performance. Renderer shows what is in use. Change it to WebGL2 only if the 3D view is empty or glitchy. The page reloads when you change it.

If you are on WebGL2 and want WebGPU, update your browser and your graphics driver first.

2. Choose the units you think in

Under Scene, Display units sets the unit for sizes and distances on screen: millimetres, centimetres, metres, inches, feet, or none. A STEP file normally comes in millimetres. This setting belongs to the open scene and is saved with it, so check it again for a scene from a different source.

Under Scene, Up axis (viewport) is Z for most CAD files and Y for glTF files and some 3D programs. It changes how the model is shown. What the exported file uses is chosen in the Export window.

3. Make it comfortable to look at

Under Appearance you can change the accent colour, the surfaces, the typeface, the text size, the roundness of corners and the height of buttons and fields. None of it touches your models. Reset at the bottom of the section puts everything back.

Under Viewport, check Background and Ground grid. Switch Outlines off if you prefer shading without edge lines.

4. Set the performance options for your computer

A fast computer, models up to a few hundred thousand triangles

Leave everything as it is.

A heavy assembly, or a modest graphics card

Keep Skip tiny parts and Lower the resolution if it stutters on. Set Quality to Low if the view still stutters.

Only the exported result matters, not the view

Make the model lighter first. See A sensible order to work in.

5. Decide how the app starts

Under General:

• Start screen and Offer the last file control whether the start screen opens with a Resume button for the file you had last.
• Splash screen is the short splash with the version number. Switch it off if you would rather have the app fade straight in.
• Warn before leaving with unsaved changes is on by default. It asks before a window with unsaved edits is closed. Leave it on.
• Undo history is 50, 200 or 500 steps. A longer history uses more memory.

6. Learn the three keys that find everything

F1

The help window: every article of this knowledge base, with a search, and it works offline.

CtrlK

Search: every menu item and every control in the sidebars, with suggestions for what is selected.

?

The list of every keyboard shortcut.

Where your settings are kept

In your browser’s storage, on this computer, not in the app folder. That has three consequences:

• They survive an update of the app.
• They are separate for each browser. The app window the launcher opens uses your usual browser profile, so an installed app in Chrome and a tab in Edge each have their own settings.
• The folder can be deleted and unpacked again without losing them. See Move, copy or remove the app.
• They belong to the address the app runs at. If the launcher ever has to choose another port than 4242, the browser treats it as a different site, and the settings seem to be gone. They come back when the app runs at its usual address again.

The buttons under Storage clear each kind of remembered thing, one at a time: the list of recent files, file permissions, the “don’t ask again” import answers, panel sizes, or all settings at once.