Even after installing missing dependencies, webapp window is blank.

sudo apt-get install qml-module-qtquick-controls qml-module-qt-labs-folderlistmodel qml-module-qt-labs-settings

$ unity-webapps-runner -n 'VGVsZWdyYW0=' -d 'zhukov.github.io' %u
** Message: Launching webapp 'Telegram' with the webapp container (command line 'webapp-container --app-id='Telegramzhukovgithubio' --webapp='VGVsZWdyYW0=' --enable-back-forward  ')
eric@pico-T60:~$ libGL error: Version 4 or later of flush extension not found
libGL error: failed to load driver: i915
The schema com.canonical.Unity.Thumbnailer is missing
Skipping "webapp-properties.json" as a webapp definition search:  "/usr/share/unity-webapps/userscripts/unity-webapps-amazon/webapp-properties.json"
Invalid webapp webapp definition: homepage not found or fails predicate isString
Could not open manifest file:  "/usr/share/unity-webapps/userscripts/unity-webapps-amazon/manifest.json"
Invalid webapps manifest found in:  "/usr/share/unity-webapps/userscripts/unity-webapps-amazon"
Skipping "webapp-properties.json" as a webapp definition search:  "/usr/share/unity-webapps/userscripts/unity-webapps-gmail/webapp-properties.json"
Skipping "webapp-properties.json" as a webapp definition search:  "/usr/share/unity-webapps/userscripts/unity-webapps-googledocs/webapp-properties.json"
Skipping "webapp-properties.json" as a webapp definition search:  "/usr/share/unity-webapps/userscripts/unity-webapps-launchpad/webapp-properties.json"
Skipping "webapp-properties.json" as a webapp definition search:  "/usr/share/unity-webapps/userscripts/unity-webapps-telegram/webapp-properties.json"
Skipping "webapp-properties.json" as a webapp definition search:  "/usr/share/unity-webapps/userscripts/unity-webapps-youtube/webapp-properties.json"
Skipping "webapp-properties.json" as a webapp definition search:  "/usr/share/unity-webapps/userscripts/unity-webapps-amazon/webapp-properties.json"
Invalid webapp webapp definition: homepage not found or fails predicate isString
Could not open manifest file:  "/usr/share/unity-webapps/userscripts/unity-webapps-amazon/manifest.json"
Invalid webapps manifest found in:  "/usr/share/unity-webapps/userscripts/unity-webapps-amazon"
Skipping "webapp-properties.json" as a webapp definition search:  "/usr/share/unity-webapps/userscripts/unity-webapps-gmail/webapp-properties.json"
Skipping "webapp-properties.json" as a webapp definition search:  "/usr/share/unity-webapps/userscripts/unity-webapps-googledocs/webapp-properties.json"
Skipping "webapp-properties.json" as a webapp definition search:  "/usr/share/unity-webapps/userscripts/unity-webapps-launchpad/webapp-properties.json"
Skipping "webapp-properties.json" as a webapp definition search:  "/usr/share/unity-webapps/userscripts/unity-webapps-telegram/webapp-properties.json"
Skipping "webapp-properties.json" as a webapp definition search:  "/usr/share/unity-webapps/userscripts/unity-webapps-youtube/webapp-properties.json"
Using Oxide as the web engine backend
Empty path in webapps model search path update request
QQmlExpression: Expression file:///usr/share/webbrowser-app/webcontainer/WebApp.qml:179:25 depends on non-NOTIFYable properties:
    unity::action::qml::ActionManager::globalContext
Empty path in webapps model search path update request
file:///usr/share/webbrowser-app/webcontainer/Chrome.qml:85: TypeError: Cannot read property 'icon' of null
file:///usr/share/webbrowser-app/webcontainer/Chrome.qml:97: TypeError: Cannot read property 'title' of null
[1111/100544:WARNING:proxy_service.cc(909)] PAC support disabled because there is no system implementation
[1111/100544:ERROR:gpu_info_collector_ozone.cc(11)] Not implemented reached in std::string gpu::CollectDriverVersionNVidia()
[1111/100544:WARNING:gpu_control_list.cc(760)] Entry with unknown fields 0
[1111/100544:WARNING:gpu_control_list.cc(746)] Malformed exceptions entry 24
qml: Loaded 2 UA override(s) from file:///usr/lib/i386-linux-gnu/qt5/qml/Ubuntu/Web/ua-overrides-desktop.js
file:///usr/lib/i386-linux-gnu/qt5/qml/Ubuntu/UnityWebApps/bindings/content-hub/backend/content-hub.js:31: ReferenceError: ContentHubBridge is not defined