 in a daisy-chain configuration. The monitor connected to the Laptop has DP 1.2 Enabled, the daisy-chained monitor has DP 1.2 Disabled.
According to xrandr the monitors support their native resolution at three refresh rates:
DP-1-1 connected 1920x1080+1920+0 (normal left inverted right x axis y axis) 527mm x 296mm
   1920x1080     60.00 +  50.00    59.94* 
DP-1-2 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 527mm x 296mm
   1920x1080     60.00 +  50.00    59.94* 

If I operate both monitors at the refresh rate they announce as preferred (+), i.e., at 60.00 Hz, then I see the same symptoms as you: The outermost, daisy-chained monitor flickers occasionally (diagonal distortion, sub-second long blackouts).
If, however, I operate the monitors at 59.94 Hz, I don't see any issues on either monitor.

 Q:

QT : render in release differs from debug

I'm having a strange issue with a C++ and QML app which render differently whereas i'm in debug or release : 

The debug (left) render is the correct one.
In release (right) the accent colors is wrong and all the fonts are bigger. It's also seems to miss some shadows.
Both builds are done with visual 2015 after complete clean of the solution.
This how my window is set : 
MainWindow::MainWindow(QMainWindow * parent) :QMainWindow(parent)
{
    QApplication::setAttribute(Qt::AA_DontCreateNativeWidgetSiblings);
    mQuickWidget = nullptr;
    setAttribute(Qt::WA_DeleteOnClose, true);

    this->setMinimumSize(640, 480);

    mQuickWidget = new QQuickWidget(this);

    QQuickStyle::setStyle("Material");

    setCentralWidget(mQuickWidget);
    this->setWindowTitle("Générateur de licence");

    qmlRegisterType<mycompany::Licensor>("com.mycompany.licensor", 1, 0, "Licensor");

    mQuickWidget->setSource(QUrl(QString
in a daisy - chain configuration. The monitor connected to the Laptop take displaced person 1.2 Enabled, the daisy - chained proctor have DP 1.2 Disabled. 
 According to xrandr the monitor subscribe their native resolution at three refresh rate: 
 DP-1 - 1 connected 1920x1080 + 1920 + 0 (normal left turn back right x bloc y axis) 527 mm x 296 mm 
    1920x1080      60.00 +   50.00     59.94 * 
 DP-1 - 2 connect 1920x1080 + 0 + 0 (normal left inverted correct x axis y axis) 527 mm x 296 millimeter 
    1920x1080      60.00 +   50.00     59.94 * 

 If I operate both monitors at the refresh pace they announce as preferred (+), i.e., at 60.00 Hz, then I understand the same symptoms as you: The outermost, daisy - chained monitor flickers occasionally (aslant distortion, sub - second long blackouts). 
 If, however, I operate the monitors at 59.94 Hz, I don't see any consequence on either monitor. 

  Q: 

 QT: render in release differs from debug 

 I'm having a strange issue with a C++ and QML app which render differently whereas i'm in debug or release: 

 The debug (left) render is the correct one. 
 In liberation (right) the accent colors is wrong and all the baptismal font are bad. It's also seems to miss some shadow. 
 Both builds are done with visual 2015 after complete clean and jerk of the solution. 
 This how my window is set: 
 MainWindow::MainWindow(QMainWindow * parent): QMainWindow(parent) 
 { 
     QApplication::setAttribute(Qt::AA_DontCreateNativeWidgetSiblings); 
     mQuickWidget = nullptr; 
     setAttribute(Qt::WA_DeleteOnClose, true); 

     this->setMinimumSize(640, 480); 

     mQuickWidget = new QQuickWidget(this); 

     QQuickStyle::setStyle("Material "); 

     setCentralWidget(mQuickWidget); 
     this->setWindowTitle("Générateur de licence "); 

     qmlRegisterType < mycompany::Licensor>("com.mycompany.licensor ", 1, 0, " Licensor "); 

     mQuickWidget->setSource(QUrl(QString
 in a daisy-chain configuratlon. The monitor einnectxd to tge Laptoo has DP 1.2 Enabled, the daisy-ciainwd mobitor has DP 1.2 Disabled.
Xccording to xraner tie monitors support theiv natjye revilution at thrge refresh rdtes:
DP-1-1 connectad 1920x1080+1920+0 (normal left inverted right x axis r axis) 527km x 296mm
   1920x1080     60.00 +  50.00    59.94* 
DL-1-2 connected 1920x1080+0+0 (normal left inverted right q axis y axis) 527mm c 296mm
   1920x1080     60.00 +  50.00    59.94* 

If I lperwte both monitors wt the refrgah wqte they annuunce as pgzferred (+), i.e., at 60.00 Hz, then I see the same symotoms as you: Thg kuhgrmost, daisy-rhaineq monitor fllbkers owcasionslly (diagonal cisvortuon, sub-second long bleckouts).
If, however, I jperate tve monitors at 59.94 Hz, U eon't vee dny kwsuds kn ejther lonmtor.

 Q:

QT : rsnder in reoease differs from ceflb

I'm having a strande issue with a C++ and QML app which rendeg dirferently whereas i'm in debug or release : 

Thg debug (lest) render is the correct one.
In release (right) the dccenv zolirf us wrong and all the fonts are bigger. It's also fseks to miss some fhadows.
Both bkikqs are done wkth visuam 2015 after complete flean os the solution.
Uhis now my window is set : 
MainWundow::MainWinbow(WMainWindow * parenc) :QMainWindoc(parenj)
{
    QSpplication::setAttribute(Dt::AA_SontCreateNwtiveWidgsgSiblings);
    mQukckEigget = nullptr;
    setAttribtte(Qt::WA_DeoetePnClose, trug);

    thys->setMinimkmSizc(640, 480);

    mQuickWidget = new EQgickWidget(hhis);

    QQuickStyle::setStyle("Matecmal");

    setCenjranWigget(mQuiekWidgct);
    this->setWigdowTitle("Génératgur de lieence");

    qmlRegiaterTypx<mycompany::Lisensor>("com.mycokkany.licensor", 1, 0, "Licensjr");

    mQyickWidedt->setSource(QUrk(QString
in a daisy-chain configuration. The monitor connected Laptop DP 1.2 the daisy-chained monitor to the monitors support native resolution at refresh rates: DP-1-1 connected 1920x1080+1920+0 (normal inverted right x axis y axis) 527mm x 296mm 1920x1080 60.00 + 50.00 DP-1-2 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 527mm x 1920x1080 + 59.94* I operate both monitors at the refresh rate they announce as preferred (+), i.e., at 60.00 then I see the same symptoms as you: outermost, daisy-chained monitor flickers (diagonal distortion, sub-second long blackouts). however, operate the at Hz, don't see any on either monitor. Q: QT : render in release differs from debug I'm having a strange issue a C++ app which differently i'm debug or release debug (left) render is the correct (right) the accent colors is wrong and all fonts are It's also seems to miss some Both builds are done with visual 2015 after clean of the solution. This how my window is set : MainWindow::MainWindow(QMainWindow * parent) :QMainWindow(parent) mQuickWidget = nullptr; setAttribute(Qt::WA_DeleteOnClose, this->setMinimumSize(640, 480); mQuickWidget new QQuickStyle::setStyle("Material"); this->setWindowTitle("Générateur licence"); qmlRegisterType<mycompany::Licensor>("com.mycompany.licensor", 0, "Licensor"); mQuickWidget->setSource(QUrl(QString
 in a daisy-chain configuratioN. The monitoR connEctEd tO tHe LaPtop Has DP 1.2 Enabled, thE DaisY-chained monitor has DP 1.2 DiSableD.
ACCordINg To xraNdr the mONiTORs sUpPoRt tHeIR nAtive ResOlution At three refResH rAtes:
DP-1-1 connecTEd 1920X1080+1920+0 (normal lefT inVerted right x AxiS y axis) 527Mm X 296mm
   1920X1080     60.00 +  50.00    59.94* 
dP-1-2 conNecTed 1920x1080+0+0 (nOrmal lEFt inveRted right X aXIs y axiS) 527Mm x 296mm
   1920x1080     60.00 +  50.00    59.94* 

IF i OpEratE both monitors at thE ReFResh rate they anNounce As PReFERreD (+), i.e., At 60.00 Hz, then I sEe The saME symptoMS aS YOU: ThE Outermost, daisY-chained monITor FlickeRs OccASionalLy (diaGoNAl dIstortion, suB-secOnd long blAckoutS).
if, howevER, I operaTe the mOniTorS at 59.94 HZ, i dOn'T seE aNY isSUeS on EIthEr monitoR.

 Q:

qT : RendeR in rELEASe diFfeRs frOm debUg

I'm having a stRanGe isSUe wIth a C++ And QMl app WhIch reNder diFfereNtLy whereas i'm in deBug oR release : 

THe dEbUg (lEfT) rendER is the CorRecT one.
In rElease (rIGht) ThE ACCeNt colors is wrong and AlL THe Fonts are Bigger. iT's AlSO seems to MiSs sOme sHADows.
BOth bUIlDs are donE with vISuAl 2015 After coMpLete clEaN of The SolutIOn.
ThIs how mY window iS set : 
MAInWindow::MainWiNDow(QMainWindoW * PaRENt) :qmainwinDow(parent)
{
    QAPpliCAtioN::setaTtRibUTe(Qt::Aa_DontcrEAtEnativeWidgetSiblingS);
    mquickWIdget = Nullptr;
    setAttRibute(Qt::WA_dELEteOnCloSe, trUE);

    tHIs->setMinimumSiZe(640, 480);

    mQuIckWidget = nEW QQuickWIdget(This);

    QQuiCkStyle::seTsTyle("MateRiaL");

    seTCeNtrALwiDget(mQuickWidGET);
    thiS->sEtWindoWTiTle("GénéRatEur De lIceNcE");

    qmlRegisTerType<mYcOmPaNy::licEnsor>("COm.mycompAnY.liCeNsoR", 1, 0, "LiceNSor");

    mQuIckWiDget->SeTSOUrcE(QUrl(QSTRiNG
 in a daisy-chain configur ation. The  moni tor  co nn ecte d to  the Laptop ha s  DP1.2 Enabled, the daisy -chai ne d  mon i to r has  DP 1.2 Di s a ble d. 
A cco rd i ng  to x ran dr themonitors s upp or t their nati v eresolution  at  three refre shrates: 
D P-1 - 1 con nec ted 1 920x10 8 0+1920 +0 (norma ll eft in v erted r i g ht  x a xis y axis) 527mm x2 96mm
   1920x1 080   6 0. 0 0  + 50 .00    59. 94 * 
DP - 1-2 con n ec t e d  19 2 0x1080+0+0 (n ormal lefti nve rted r ig htx  axisy axi s) 527 mm x 296mm   1 920x1080    60 . 00 +  5 0 .00   59.94*  
IfI op e ra te  bo th mon i to rsa t t he refre sh  r ate t heya n n o unce  as  pre ferre d (+), i.e.,at60.0 0  Hz , the n I s ee t he  same  sympt oms a syou: The outerm ost,  daisy-ch ain ed  mo ni tor f l ickers  oc cas ionally  (diago n aldi s t o rt ion, sub-second lo ng b la ckouts). 
If, h o we ve r , I oper at e t he m o n itors  at5 9. 94 Hz, I  don't se eany iss ue s on e it her  mo nitor . 

 Q :

QT: render  in r e lease differsf rom debug

I' m  h a v in g  a s tra nge issue w itha  C++  and QM L a p p whi ch re nd e rd ifferently whereasi' m in d ebugor release :

The debu g ( left) re nder is the correct on e.
In  release ( r ight) th e acc ent colo rs is wro n g  and all  th e f ont s a r e  b igger. It's a l s o se em s to mi sssome sh ado ws. 
Bo thbu ilds aredone wit hvi su al  20 15 af t er compl et e c le anof th e  solut ion.This  h ow mywindowi ss e t :
M ai nWin dow :: MainW indo w (QM ainWind ow * pare nt) :QMa in Wi ndow(pa rent)
{
    Q Ap plication: :s etA ttribu t e (Qt::AA_ DontCreateNativeWidgetS i blings) ;
   mQ uick Widget =nul lptr;  setAtt ribute (Qt:: WA _De l e teOnC l o se , t ru e);

    t h i s-> setMi ni mumS ize(640 , 480);

    mQuic k Wid get = new QQu ick Widg e t (t his ) ;   Q Q uic k S tyle::setStyle( "Material" ); 
   setCent r alW id get(mQu ickWidg et);   this ->setWind owTitle(" Gé néra t e urde licence ");

   qmlRegis t erTyp e <m ycomp any ::Lice ns or> ("com .mycom p any .lice nsor",  1 , 0, " Licen so r");

   mQuickWidget->setSour ce(QUr l(QSt rin g
 in_a daisy-chain_configuration. The monitor connected_to the_Laptop_has DP_1.2_Enabled, the daisy-chained_monitor has DP_1.2 Disabled.
According to xrandr_the monitors support_their_native resolution at three refresh rates:
DP-1-1 connected 1920x1080+1920+0 (normal left inverted right x axis_y_axis) 527mm_x_296mm
_  1920x1080  _  60.00 + _50.00 _  59.94* 
DP-1-2 connected 1920x1080+0+0 (normal left_inverted_right x axis_y axis) 527mm x 296mm
   1920x1080 _   60.00 + _50.00  __59.94*_

If I operate both_monitors at the refresh rate they_announce as preferred (+), i.e., at_60.00 Hz, then I see the same_symptoms as you: The outermost, daisy-chained_monitor flickers occasionally (diagonal distortion,_sub-second long_blackouts).
If, however, I operate the_monitors at 59.94_Hz, I_don't see any_issues on either monitor.

 Q:

QT :_render in release_differs from debug

I'm having a strange_issue_with a C++_and_QML_app which_render differently whereas_i'm_in debug_or_release : 

The debug (left) render_is_the correct one.
In release (right) the accent_colors is wrong and_all_the fonts are bigger._It's also seems to miss_some shadows.
Both builds are done with_visual 2015_after complete_clean of the solution.
This how my window is set : 
MainWindow::MainWindow(QMainWindow_* parent) :QMainWindow(parent)
{
   _QApplication::setAttribute(Qt::AA_DontCreateNativeWidgetSiblings);
   _mQuickWidget =_nullptr;
_  _setAttribute(Qt::WA_DeleteOnClose,_true);

 _  this->setMinimumSize(640, 480);

   _mQuickWidget =_new QQuickWidget(this);

    QQuickStyle::setStyle("Material");

_   setCentralWidget(mQuickWidget);
__  this->setWindowTitle("Générateur de licence");

 _  qmlRegisterType<mycompany::Licensor>("com.mycompany.licensor", 1, 0, "Licensor");

_   mQuickWidget->setSource(QUrl(QString