diff --git a/src/server/surface_interface.cpp b/src/server/surface_interface.cpp
index 8338f8d..82d4846 100644
--- a/src/server/surface_interface.cpp
+++ b/src/server/surface_interface.cpp
@@ -1,664 +1,669 @@
 /********************************************************************
 Copyright 2014  Martin Gräßlin <mgraesslin@kde.org>
 
 This library is free software; you can redistribute it and/or
 modify it under the terms of the GNU Lesser General Public
 License as published by the Free Software Foundation; either
 version 2.1 of the License, or (at your option) version 3, or any
 later version accepted by the membership of KDE e.V. (or its
 successor approved by the membership of KDE e.V.), which shall
 act as a proxy defined in Section 6 of version 3 of the license.
 
 This library is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 Lesser General Public License for more details.
 
 You should have received a copy of the GNU Lesser General Public
 License along with this library.  If not, see <http://www.gnu.org/licenses/>.
 *********************************************************************/
 #include "surface_interface.h"
 #include "surface_interface_p.h"
 #include "buffer_interface.h"
 #include "clientconnection.h"
 #include "compositor_interface.h"
 #include "region_interface.h"
 #include "subcompositor_interface.h"
 #include "subsurface_interface_p.h"
 // Wayland
 #include <wayland-server.h>
 // std
 #include <algorithm>
 
 namespace KWayland
 {
 namespace Server
 {
 
 SurfaceInterface::Private::Private(SurfaceInterface *q, CompositorInterface *c, wl_resource *parentResource)
     : Resource::Private(q, c, parentResource, &wl_surface_interface, &s_interface)
 {
 }
 
 SurfaceInterface::Private::~Private()
 {
     destroy();
 }
 
 void SurfaceInterface::Private::addChild(QPointer< SubSurfaceInterface > child)
 {
     // protocol is not precise on how to handle the addition of new sub surfaces
     pending.children.append(child);
     subSurfacePending.children.append(child);
     current.children.append(child);
     Q_Q(SurfaceInterface);
     emit q->subSurfaceTreeChanged();
     QObject::connect(child.data(), &SubSurfaceInterface::positionChanged, q, &SurfaceInterface::subSurfaceTreeChanged);
     QObject::connect(child->surface().data(), &SurfaceInterface::damaged, q, &SurfaceInterface::subSurfaceTreeChanged);
     QObject::connect(child->surface().data(), &SurfaceInterface::unmapped, q, &SurfaceInterface::subSurfaceTreeChanged);
     QObject::connect(child->surface().data(), &SurfaceInterface::subSurfaceTreeChanged, q, &SurfaceInterface::subSurfaceTreeChanged);
 }
 
 void SurfaceInterface::Private::removeChild(QPointer< SubSurfaceInterface > child)
 {
     // protocol is not precise on how to handle the addition of new sub surfaces
     pending.children.removeAll(child);
     subSurfacePending.children.removeAll(child);
     current.children.removeAll(child);
     Q_Q(SurfaceInterface);
     emit q->subSurfaceTreeChanged();
     QObject::disconnect(child.data(), &SubSurfaceInterface::positionChanged, q, &SurfaceInterface::subSurfaceTreeChanged);
     QObject::disconnect(child->surface().data(), &SurfaceInterface::damaged, q, &SurfaceInterface::subSurfaceTreeChanged);
     QObject::disconnect(child->surface().data(), &SurfaceInterface::unmapped, q, &SurfaceInterface::subSurfaceTreeChanged);
     QObject::disconnect(child->surface().data(), &SurfaceInterface::subSurfaceTreeChanged, q, &SurfaceInterface::subSurfaceTreeChanged);
 }
 
 bool SurfaceInterface::Private::raiseChild(QPointer<SubSurfaceInterface> subsurface, SurfaceInterface *sibling)
 {
     Q_Q(SurfaceInterface);
     auto it = std::find(pending.children.begin(), pending.children.end(), subsurface);
     if (it == pending.children.end()) {
         return false;
     }
     if (pending.children.count() == 1) {
         // nothing to do
         return true;
     }
     if (sibling == q) {
         // it's to the parent, so needs to become last item
         pending.children.append(*it);
         pending.children.erase(it);
         pending.childrenChanged = true;
         return true;
     }
     if (!sibling->subSurface()) {
         // not a sub surface
         return false;
     }
     auto siblingIt = std::find(pending.children.begin(), pending.children.end(), sibling->subSurface());
     if (siblingIt == pending.children.end() || siblingIt == it) {
         // not a sibling
         return false;
     }
     auto value = (*it);
     pending.children.erase(it);
     // find the iterator again
     siblingIt = std::find(pending.children.begin(), pending.children.end(), sibling->subSurface());
     pending.children.insert(++siblingIt, value);
     pending.childrenChanged = true;
     return true;
 }
 
 bool SurfaceInterface::Private::lowerChild(QPointer<SubSurfaceInterface> subsurface, SurfaceInterface *sibling)
 {
     Q_Q(SurfaceInterface);
     auto it = std::find(pending.children.begin(), pending.children.end(), subsurface);
     if (it == pending.children.end()) {
         return false;
     }
     if (pending.children.count() == 1) {
         // nothing to do
         return true;
     }
     if (sibling == q) {
         // it's to the parent, so needs to become first item
         auto value = *it;
         pending.children.erase(it);
         pending.children.prepend(value);
         pending.childrenChanged = true;
         return true;
     }
     if (!sibling->subSurface()) {
         // not a sub surface
         return false;
     }
     auto siblingIt = std::find(pending.children.begin(), pending.children.end(), sibling->subSurface());
     if (siblingIt == pending.children.end() || siblingIt == it) {
         // not a sibling
         return false;
     }
     auto value = (*it);
     pending.children.erase(it);
     // find the iterator again
     siblingIt = std::find(pending.children.begin(), pending.children.end(), sibling->subSurface());
     pending.children.insert(siblingIt, value);
     pending.childrenChanged = true;
     return true;
 }
 
 void SurfaceInterface::Private::setShadow(const QPointer<ShadowInterface> &shadow)
 {
     pending.shadow = shadow;
     pending.shadowIsSet = true;
 }
 
 void SurfaceInterface::Private::setBlur(const QPointer<BlurInterface> &blur)
 {
     pending.blur = blur;
     pending.blurIsSet = true;
 }
 
 void SurfaceInterface::Private::setSlide(const QPointer<SlideInterface> &slide)
 {
     pending.slide = slide;
     pending.slideIsSet = true;
 }
 
 void SurfaceInterface::Private::setContrast(const QPointer<ContrastInterface> &contrast)
 {
     pending.contrast = contrast;
     pending.contrastIsSet = true;
 }
 
 #ifndef DOXYGEN_SHOULD_SKIP_THIS
 const struct wl_surface_interface SurfaceInterface::Private::s_interface = {
     destroyCallback,
     attachCallback,
     damageCallback,
     frameCallaback,
     opaqueRegionCallback,
     inputRegionCallback,
     commitCallback,
     bufferTransformCallback,
     bufferScaleCallback
 };
 #endif
 
 SurfaceInterface::SurfaceInterface(CompositorInterface *parent, wl_resource *parentResource)
     : Resource(new Private(this, parent, parentResource))
 {
 }
 
 SurfaceInterface::~SurfaceInterface() = default;
 
 void SurfaceInterface::frameRendered(quint32 msec)
 {
     Q_D();
     // notify all callbacks
     const bool needsFlush = !d->current.callbacks.isEmpty();
     while (!d->current.callbacks.isEmpty()) {
         wl_resource *r = d->current.callbacks.takeFirst();
         wl_callback_send_done(r, msec);
         wl_resource_destroy(r);
     }
     for (auto it = d->current.children.constBegin(); it != d->current.children.constEnd(); ++it) {
         const auto &subSurface = *it;
         if (subSurface.isNull() || subSurface->d_func()->surface.isNull()) {
             continue;
         }
         subSurface->d_func()->surface->frameRendered(msec);
     }
     if (needsFlush)  {
         client()->flush();
     }
 }
 
 void SurfaceInterface::Private::destroy()
 {
     for (wl_resource *c : current.callbacks) {
         wl_resource_destroy(c);
     }
     for (wl_resource *c : pending.callbacks) {
         wl_resource_destroy(c);
     }
     for (wl_resource *c : subSurfacePending.callbacks) {
         wl_resource_destroy(c);
     }
     if (current.buffer) {
         current.buffer->unref();
     }
     if (resource) {
         wl_resource_destroy(resource);
         resource = nullptr;
     }
 }
 
 void SurfaceInterface::Private::swapStates(State *source, State *target, bool emitChanged)
 {
     Q_Q(SurfaceInterface);
     const bool bufferChanged = source->bufferIsSet;
     const bool opaqueRegionChanged = source->opaqueIsSet;
     const bool inputRegionChanged = source->inputIsSet;
     const bool scaleFactorChanged = source->scaleIsSet && (target->scale != source->scale);
     const bool transformChanged = source->transformIsSet && (target->transform != source->transform);
     const bool shadowChanged = source->shadowIsSet;
     const bool blurChanged = source->blurIsSet;
     const bool contrastChanged = source->contrastIsSet;
     const bool slideChanged = source->slideIsSet;
     const bool childrenChanged = source->childrenChanged;
     bool sizeChanged = false;
     auto buffer = target->buffer;
     if (bufferChanged) {
         // TODO: is the reffing correct for subsurfaces?
         QSize oldSize;
         if (target->buffer) {
             oldSize = target->buffer->size();
             if (emitChanged) {
                 target->buffer->unref();
                 QObject::disconnect(target->buffer, &BufferInterface::sizeChanged, q, &SurfaceInterface::sizeChanged);
             } else {
                 delete target->buffer;
                 target->buffer = nullptr;
             }
         }
         if (source->buffer) {
             if (emitChanged) {
                 source->buffer->ref();
                 QObject::connect(source->buffer, &BufferInterface::sizeChanged, q, &SurfaceInterface::sizeChanged);
             }
             const QSize newSize = source->buffer->size();
             sizeChanged = newSize.isValid() && newSize != oldSize;
         }
         buffer = source->buffer;
     }
     // copy values
     if (bufferChanged) {
         target->buffer = buffer;
         target->damage = source->damage;
         target->bufferIsSet = source->bufferIsSet;
     }
     if (childrenChanged) {
         target->childrenChanged = source->childrenChanged;
         target->children = source->children;
     }
     target->callbacks.append(source->callbacks);
 
     if (shadowChanged) {
         target->shadow = source->shadow;
         target->shadowIsSet = true;
     }
     if (blurChanged) {
         target->blur = source->blur;
         target->blurIsSet = true;
     }
     if (contrastChanged) {
         target->contrast = source->contrast;
         target->contrastIsSet = true;
     }
     if (slideChanged) {
         target->slide = source->slide;
         target->slideIsSet = true;
     }
     if (inputRegionChanged) {
         target->input = source->input;
         target->inputIsInfinite = source->inputIsInfinite;
         target->inputIsSet = true;
     }
     if (opaqueRegionChanged) {
         target->opaque = source->opaque;
         target->opaqueIsSet = true;
     }
     if (scaleFactorChanged) {
         target->scale = source->scale;
         target->scaleIsSet = true;
     }
     if (transformChanged) {
         target->transform = source->transform;
         target->transformIsSet = true;
     }
 
     *source = State{};
     source->children = target->children;
     if (opaqueRegionChanged) {
         emit q->opaqueChanged(target->opaque);
     }
     if (inputRegionChanged) {
         emit q->inputChanged(target->input);
     }
     if (scaleFactorChanged) {
         emit q->scaleChanged(target->scale);
     }
     if (transformChanged) {
         emit q->transformChanged(target->transform);
     }
     if (bufferChanged && emitChanged) {
         if (!target->damage.isEmpty()) {
             const QRegion windowRegion = QRegion(0, 0, q->size().width(), q->size().height());
             if (!windowRegion.isEmpty()) {
                 target->damage = windowRegion.intersected(target->damage);
                 if (emitChanged) {
                     emit q->damaged(target->damage);
+                    // workaround for https://bugreports.qt.io/browse/QTBUG-52092
+                    // if the surface is a sub-surface, but the main surface is not yet mapped, fake frame rendered
+                    if (subSurface && !subSurface->mainSurface()->buffer()) {
+                        q->frameRendered(0);
+                    }
                 }
             }
         } else if (!target->buffer && emitChanged) {
             emit q->unmapped();
         }
     }
     if (!emitChanged) {
         return;
     }
     if (sizeChanged) {
         emit q->sizeChanged();
     }
     if (shadowChanged) {
         emit q->shadowChanged();
     }
     if (blurChanged) {
         emit q->blurChanged();
     }
     if (contrastChanged) {
         emit q->contrastChanged();
     }
     if (slideChanged) {
         emit q->slideOnShowHideChanged();
     }
     if (childrenChanged) {
         emit q->subSurfaceTreeChanged();
     }
 }
 
 void SurfaceInterface::Private::commit()
 {
     if (!subSurface.isNull() && subSurface->isSynchronized()) {
         swapStates(&pending, &subSurfacePending, false);
     } else {
         swapStates(&pending, &current, true);
         if (!subSurface.isNull()) {
             subSurface->d_func()->commit();
         }
         // commit all subSurfaces to apply position changes
         // "The cached state is applied to the sub-surface immediately after the parent surface's state is applied"
         for (auto it = current.children.constBegin(); it != current.children.constEnd(); ++it) {
             const auto &subSurface = *it;
             if (subSurface.isNull()) {
                 continue;
             }
             subSurface->d_func()->commit();
         }
     }
 }
 
 void SurfaceInterface::Private::commitSubSurface()
 {
     if (subSurface.isNull() || !subSurface->isSynchronized()) {
         return;
     }
     swapStates(&subSurfacePending, &current, true);
     // "The cached state is applied to the sub-surface immediately after the parent surface's state is applied"
     for (auto it = current.children.constBegin(); it != current.children.constEnd(); ++it) {
         const auto &subSurface = *it;
         if (subSurface.isNull() || !subSurface->isSynchronized()) {
             continue;
         }
         subSurface->d_func()->commit();
     }
 }
 
 void SurfaceInterface::Private::damage(const QRect &rect)
 {
     if (!pending.bufferIsSet || (pending.bufferIsSet && !pending.buffer)) {
         // TODO: should we send an error?
         return;
     }
     pending.damage = pending.damage.united(rect);
 }
 
 void SurfaceInterface::Private::setScale(qint32 scale)
 {
     pending.scale = scale;
     pending.scaleIsSet = true;
 }
 
 void SurfaceInterface::Private::setTransform(OutputInterface::Transform transform)
 {
     pending.transform = transform;
 }
 
 void SurfaceInterface::Private::addFrameCallback(uint32_t callback)
 {
     wl_resource *r = client->createResource(&wl_callback_interface, 1, callback);
     if (!r) {
         wl_resource_post_no_memory(resource);
         return;
     }
     wl_resource_set_implementation(r, nullptr, this, destroyFrameCallback);
     pending.callbacks << r;
 }
 
 void SurfaceInterface::Private::attachBuffer(wl_resource *buffer, const QPoint &offset)
 {
     pending.bufferIsSet = true;
     pending.offset = offset;
     if (pending.buffer) {
         delete pending.buffer;
     }
     if (!buffer) {
         // got a null buffer, deletes content in next frame
         pending.buffer = nullptr;
         pending.damage = QRegion();
         return;
     }
     Q_Q(SurfaceInterface);
     pending.buffer = new BufferInterface(buffer, q);
     QObject::connect(pending.buffer, &BufferInterface::aboutToBeDestroyed, q,
         [this](BufferInterface *buffer) {
             if (pending.buffer == buffer) {
                 pending.buffer = nullptr;
             }
             if (subSurfacePending.buffer == buffer) {
                 subSurfacePending.buffer = nullptr;
             }
             if (current.buffer == buffer) {
                 current.buffer->unref();
                 current.buffer = nullptr;
             }
         }
     );
 }
 
 void SurfaceInterface::Private::destroyFrameCallback(wl_resource *r)
 {
     auto s = cast<Private>(r);
     s->current.callbacks.removeAll(r);
     s->pending.callbacks.removeAll(r);
     s->subSurfacePending.callbacks.removeAll(r);
 }
 
 void SurfaceInterface::Private::destroyCallback(wl_client *client, wl_resource *resource)
 {
     Q_UNUSED(client)
     wl_resource_destroy(resource);
 }
 
 void SurfaceInterface::Private::attachCallback(wl_client *client, wl_resource *resource, wl_resource *buffer, int32_t sx, int32_t sy)
 {
     Q_UNUSED(client)
     cast<Private>(resource)->attachBuffer(buffer, QPoint(sx, sy));
 }
 
 void SurfaceInterface::Private::damageCallback(wl_client *client, wl_resource *resource, int32_t x, int32_t y, int32_t width, int32_t height)
 {
     Q_UNUSED(client)
     cast<Private>(resource)->damage(QRect(x, y, width, height));
 }
 
 void SurfaceInterface::Private::frameCallaback(wl_client *client, wl_resource *resource, uint32_t callback)
 {
     auto s = cast<Private>(resource);
     Q_ASSERT(client == *s->client);
     s->addFrameCallback(callback);
 }
 
 void SurfaceInterface::Private::opaqueRegionCallback(wl_client *client, wl_resource *resource, wl_resource *region)
 {
     auto s = cast<Private>(resource);
     Q_ASSERT(client == *s->client);
     auto r = RegionInterface::get(region);
     s->setOpaque(r ? r->region() : QRegion());
 }
 
 void SurfaceInterface::Private::setOpaque(const QRegion &region)
 {
     pending.opaqueIsSet = true;
     pending.opaque = region;
 }
 
 void SurfaceInterface::Private::inputRegionCallback(wl_client *client, wl_resource *resource, wl_resource *region)
 {
     auto s = cast<Private>(resource);
     Q_ASSERT(client == *s->client);
     auto r = RegionInterface::get(region);
     s->setInput(r ? r->region() : QRegion(), !r);
 }
 
 void SurfaceInterface::Private::setInput(const QRegion &region, bool isInfinite)
 {
     pending.inputIsSet = true;
     pending.inputIsInfinite = isInfinite;
     pending.input = region;
 }
 
 void SurfaceInterface::Private::commitCallback(wl_client *client, wl_resource *resource)
 {
     Q_UNUSED(client)
     cast<Private>(resource)->commit();
 }
 
 void SurfaceInterface::Private::bufferTransformCallback(wl_client *client, wl_resource *resource, int32_t transform)
 {
     Q_UNUSED(client)
     cast<Private>(resource)->setTransform(OutputInterface::Transform(transform));
 }
 
 void SurfaceInterface::Private::bufferScaleCallback(wl_client *client, wl_resource *resource, int32_t scale)
 {
     Q_UNUSED(client)
     cast<Private>(resource)->setScale(scale);
 }
 
 QRegion SurfaceInterface::damage() const
 {
     Q_D();
     return d->current.damage;
 }
 
 QRegion SurfaceInterface::opaque() const
 {
     Q_D();
     return d->current.opaque;
 }
 
 QRegion SurfaceInterface::input() const
 {
     Q_D();
     return d->current.input;
 }
 
 bool SurfaceInterface::inputIsInfitine() const
 {
     return inputIsInfinite();
 }
 
 bool SurfaceInterface::inputIsInfinite() const
 {
     Q_D();
     return d->current.inputIsInfinite;
 }
 
 qint32 SurfaceInterface::scale() const
 {
     Q_D();
     return d->current.scale;
 }
 
 OutputInterface::Transform SurfaceInterface::transform() const
 {
     Q_D();
     return d->current.transform;
 }
 
 BufferInterface *SurfaceInterface::buffer()
 {
     Q_D();
     return d->current.buffer;
 }
 
 QPoint SurfaceInterface::offset() const
 {
     Q_D();
     return d->current.offset;
 }
 
 SurfaceInterface *SurfaceInterface::get(wl_resource *native)
 {
     return Private::get<SurfaceInterface>(native);
 }
 
 SurfaceInterface *SurfaceInterface::get(quint32 id, const ClientConnection *client)
 {
     return Private::get<SurfaceInterface>(id, client);
 }
 
 QList< QPointer< SubSurfaceInterface > > SurfaceInterface::childSubSurfaces() const
 {
     Q_D();
     return d->current.children;
 }
 
 QPointer< SubSurfaceInterface > SurfaceInterface::subSurface() const
 {
     Q_D();
     return d->subSurface;
 }
 
 QSize SurfaceInterface::size() const
 {
     Q_D();
     // TODO: apply transform and scale to the buffer size
     if (d->current.buffer) {
         return d->current.buffer->size();
     }
     return QSize();
 }
 
 QPointer< ShadowInterface > SurfaceInterface::shadow() const
 {
     Q_D();
     return d->current.shadow;
 }
 
 QPointer< BlurInterface > SurfaceInterface::blur() const
 {
     Q_D();
     return d->current.blur;
 }
 
 QPointer< ContrastInterface > SurfaceInterface::contrast() const
 {
     Q_D();
     return d->current.contrast;
 }
 
 QPointer< SlideInterface > SurfaceInterface::slideOnShowHide() const
 {
     Q_D();
     return d->current.slide;
 }
 
 SurfaceInterface::Private *SurfaceInterface::d_func() const
 {
     return reinterpret_cast<Private*>(d.data());
 }
 
 }
 }