The forceOwnRefreshDriver attribute is only used by devtools iframes:

• for the toolbox window host iframe searchfox
• for tools iframes searchfox

This attribute was added in Bug 832920 to avoid a Windows-only graphical glitch: CSS transitions would stop working after swapping from a docked host to a separate window host.

Setting the attribute on the iframe avoids running

  if (!containingElement->IsXULElement() ||
      !containingElement->HasAttr(kNameSpaceID_None,
                                  nsGkAtoms::forceOwnRefreshDriver)) {
    mRefreshDriver = parent->GetPresContext()->RefreshDriver();
  }

searchfox

which will then force:

if (!mRefreshDriver) {
  mRefreshDriver = new nsRefreshDriver(this);
  if (XRE_IsContentProcess()) {
    mRefreshDriver->InitializeTimer();
  }
}

We should check if the bug is still valid and if we should keep the attribute.