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### Issue Details
Electron Version: All Version
Operating System: macOS 10.15.3
Last Known Working Electron version: Never

### Bug
The color picker in devtools does not work.
In devtools if you want to change the colors of the CSS code. When you click on a color a color picker is supposed to appear but it does not appear.

### Screenshots
<img width="1013" alt="Capture d’écran 2020-09-07 à 11 42 44" src="https://user-images.githubusercontent.com/70572698/92374841-988ea280-f100-11ea-96be-afc93f6dd645.png">

shell/browser/api/electron_api_web_contents.cc
if (CanGoToIndex(index))
    ontents()->GetController().GoToIndex(index);
}
int WebContents::GetActiveIndex() const {
  return ontents()->GetController().GetCurrentEntryIndex();
}
void WebContents::ClearHistory() {
   In some rare cases (normally while there is no real history) we are in a
   state where we can't prune navigation entries
  if (ontents()->GetController().CanPruneAllButLastCommitted()) {
    ontents()->GetController().PruneAllButLastCommitted();
  }
}
int WebContents::GetHistoryLength() const {
  return ontents()->GetController().GetEntryCount();
}
const std::string WebContents::GetWebRTCIPHandlingPolicy() const {
  return ontents()->GetMutableRendererPrefs()->webrtc_ip_handling_policy;
}
void WebContents::SetWebRTCIPHandlingPolicy(
    const std::string& webrtc_ip_handling_policy) {
  if (GetWebRTCIPHandlingPolicy() == webrtc_ip_handling_policy)
    return;
  ontents()->GetMutableRendererPrefs()->webrtc_ip_handling_policy =
      webrtc_ip_handling_policy;
  ontents()->SyncRendererPrefs();
}
bool WebContents::IsCrashed() const {