These are the known issues in terms of support for various browser capabilities. In future versions some of these might be resolved.
Popups are allowed but are not synced between panes.
Shortcuts for non-qwerty keyboards on Mac
Unfortunately, keyboard shortcuts on Mac assume a qwerty layout so won't work well in e.g. a Dvorak or Azerty layout, due to a bug in Electorn, which Polypane uses. We're actively working towards a solution for this.
Polypane's implementation of history.replaceState does not yet follow the specification and will add an entry into your history list.
macOS visual artifacts
Sometimes macOS will display weird artifacts over the UI, this is a known issue in the Chromium rendering engine. To work around this you can disable hardware emulation from the "view" menu.
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