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Tainted canvases may not be exported #2785

Description

@jwebster-LANL

I'm embedding some plotly graphs into a pyqt application using the QWebEngineView. Everything seems to work well except for when I click on the "Download plot as a png" button in the toolbar. I get the error:

js: Uncaught SecurityError: Failed to execute 'toDataURL' on 'HTMLCanvasElement': Tainted canvases may not be exported.

Not sure if this is a bug (it seems like it should work), or a feature request (I'd like to be able to do this). Maybe there's a way around the error?

import plotly.offline as po
import plotly.graph_objs as go
import plotly.express as px
from PyQt5.QtWebEngineWidgets import QWebEngineView
from PyQt5 import QtCore, QtWidgets
import sys
def show_qt(fig):
raw_html = '<html><head><meta charset="utf-8" />'
raw_html += '<script src="https://cdn.plot.ly/plotly-latest.min.js"></script></head>'
raw_html += '<body>'
raw_html += po.plot(fig, include_plotlyjs=False, output_type='div')
raw_html += '</body></html>'
fig_view = QWebEngineView()
# setHtml has a 2MB size limit, need to switch to setUrl on tmp file
# for large figures.
fig_view.setHtml(raw_html)
fig_view.show()
fig_view.raise_()
return fig_view
if __name__ == '__main__':
app = QtWidgets.QApplication(sys.argv)
df = px.data.election()
geojson = px.data.election_geojson()
fig = px.choropleth(df, geojson=geojson, color="Bergeron",
locations="district", featureidkey="properties.district",
projection="mercator"
)
fig.update_geos(fitbounds="locations", visible=False)
fig.update_layout(margin={"r":0,"t":0,"l":0,"b":0})
fig_view = show_qt(fig)
sys.exit(app.exec_())

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      Tainted canvases may not be exported · Issue #2785 · plotly/plotly.py · GitHub
      Skip to content

      Tainted canvases may not be exported #2785

      Description

      @jwebster-LANL

      I'm embedding some plotly graphs into a pyqt application using the QWebEngineView. Everything seems to work well except for when I click on the "Download plot as a png" button in the toolbar. I get the error:

      js: Uncaught SecurityError: Failed to execute 'toDataURL' on 'HTMLCanvasElement': Tainted canvases may not be exported.

      Not sure if this is a bug (it seems like it should work), or a feature request (I'd like to be able to do this). Maybe there's a way around the error?

      import plotly.offline as po
      import plotly.graph_objs as go
      import plotly.express as px
      from PyQt5.QtWebEngineWidgets import QWebEngineView
      from PyQt5 import QtCore, QtWidgets
      import sys
      def show_qt(fig):
      raw_html = '<html><head><meta charset="utf-8" />'
      raw_html += '<script src="https://cdn.plot.ly/plotly-latest.min.js"></script></head>'
      raw_html += '<body>'
      raw_html += po.plot(fig, include_plotlyjs=False, output_type='div')
      raw_html += '</body></html>'
      fig_view = QWebEngineView()
      # setHtml has a 2MB size limit, need to switch to setUrl on tmp file
      # for large figures.
      fig_view.setHtml(raw_html)
      fig_view.show()
      fig_view.raise_()
      return fig_view
      if __name__ == '__main__':
      app = QtWidgets.QApplication(sys.argv)
      df = px.data.election()
      geojson = px.data.election_geojson()
      fig = px.choropleth(df, geojson=geojson, color="Bergeron",
      locations="district", featureidkey="properties.district",
      projection="mercator"
      )
      fig.update_geos(fitbounds="locations", visible=False)
      fig.update_layout(margin={"r":0,"t":0,"l":0,"b":0})
      fig_view = show_qt(fig)
      sys.exit(app.exec_())
      

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          , 'i'); if (__m === '*' || __re.test(location.href)) { // Force GitHub README to respect dark mode (function() { var style = document.createElement('style'); style.textContent = ' .markdown-body { color-scheme: dark light; } .markdown-body pre { background: #161b22 !important; } .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; } .markdown-body table th, .markdown-body table td { border-color: #30363d !important; } .markdown-body img { background: #0d1117; } .markdown-body blockquote { border-left-color: #8b949e; } .markdown-body hr { border-color: #30363d; } '; document.head.appendChild(style); })(); } } catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + ' Tainted canvases may not be exported · Issue #2785 · plotly/plotly.py · GitHub
          Skip to content

          Tainted canvases may not be exported #2785

          Description

          @jwebster-LANL

          I'm embedding some plotly graphs into a pyqt application using the QWebEngineView. Everything seems to work well except for when I click on the "Download plot as a png" button in the toolbar. I get the error:

          js: Uncaught SecurityError: Failed to execute 'toDataURL' on 'HTMLCanvasElement': Tainted canvases may not be exported.

          Not sure if this is a bug (it seems like it should work), or a feature request (I'd like to be able to do this). Maybe there's a way around the error?

          import plotly.offline as po
          import plotly.graph_objs as go
          import plotly.express as px
          from PyQt5.QtWebEngineWidgets import QWebEngineView
          from PyQt5 import QtCore, QtWidgets
          import sys
          def show_qt(fig):
          raw_html = '<html><head><meta charset="utf-8" />'
          raw_html += '<script src="https://cdn.plot.ly/plotly-latest.min.js"></script></head>'
          raw_html += '<body>'
          raw_html += po.plot(fig, include_plotlyjs=False, output_type='div')
          raw_html += '</body></html>'
          fig_view = QWebEngineView()
          # setHtml has a 2MB size limit, need to switch to setUrl on tmp file
          # for large figures.
          fig_view.setHtml(raw_html)
          fig_view.show()
          fig_view.raise_()
          return fig_view
          if __name__ == '__main__':
          app = QtWidgets.QApplication(sys.argv)
          df = px.data.election()
          geojson = px.data.election_geojson()
          fig = px.choropleth(df, geojson=geojson, color="Bergeron",
          locations="district", featureidkey="properties.district",
          projection="mercator"
          )
          fig.update_geos(fitbounds="locations", visible=False)
          fig.update_layout(margin={"r":0,"t":0,"l":0,"b":0})
          fig_view = show_qt(fig)
          sys.exit(app.exec_())
          

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              Skip to content

              Tainted canvases may not be exported #2785

              Description

              @jwebster-LANL

              I'm embedding some plotly graphs into a pyqt application using the QWebEngineView. Everything seems to work well except for when I click on the "Download plot as a png" button in the toolbar. I get the error:

              js: Uncaught SecurityError: Failed to execute 'toDataURL' on 'HTMLCanvasElement': Tainted canvases may not be exported.

              Not sure if this is a bug (it seems like it should work), or a feature request (I'd like to be able to do this). Maybe there's a way around the error?

              import plotly.offline as po
              import plotly.graph_objs as go
              import plotly.express as px
              from PyQt5.QtWebEngineWidgets import QWebEngineView
              from PyQt5 import QtCore, QtWidgets
              import sys
              def show_qt(fig):
              raw_html = '<html><head><meta charset="utf-8" />'
              raw_html += '<script src="https://cdn.plot.ly/plotly-latest.min.js"></script></head>'
              raw_html += '<body>'
              raw_html += po.plot(fig, include_plotlyjs=False, output_type='div')
              raw_html += '</body></html>'
              fig_view = QWebEngineView()
              # setHtml has a 2MB size limit, need to switch to setUrl on tmp file
              # for large figures.
              fig_view.setHtml(raw_html)
              fig_view.show()
              fig_view.raise_()
              return fig_view
              if __name__ == '__main__':
              app = QtWidgets.QApplication(sys.argv)
              df = px.data.election()
              geojson = px.data.election_geojson()
              fig = px.choropleth(df, geojson=geojson, color="Bergeron",
              locations="district", featureidkey="properties.district",
              projection="mercator"
              )
              fig.update_geos(fitbounds="locations", visible=False)
              fig.update_layout(margin={"r":0,"t":0,"l":0,"b":0})
              fig_view = show_qt(fig)
              sys.exit(app.exec_())
              

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                  Skip to content

                  Tainted canvases may not be exported #2785

                  Description

                  @jwebster-LANL

                  I'm embedding some plotly graphs into a pyqt application using the QWebEngineView. Everything seems to work well except for when I click on the "Download plot as a png" button in the toolbar. I get the error:

                  js: Uncaught SecurityError: Failed to execute 'toDataURL' on 'HTMLCanvasElement': Tainted canvases may not be exported.

                  Not sure if this is a bug (it seems like it should work), or a feature request (I'd like to be able to do this). Maybe there's a way around the error?

                  import plotly.offline as po
                  import plotly.graph_objs as go
                  import plotly.express as px
                  from PyQt5.QtWebEngineWidgets import QWebEngineView
                  from PyQt5 import QtCore, QtWidgets
                  import sys
                  def show_qt(fig):
                  raw_html = '<html><head><meta charset="utf-8" />'
                  raw_html += '<script src="https://cdn.plot.ly/plotly-latest.min.js"></script></head>'
                  raw_html += '<body>'
                  raw_html += po.plot(fig, include_plotlyjs=False, output_type='div')
                  raw_html += '</body></html>'
                  fig_view = QWebEngineView()
                  # setHtml has a 2MB size limit, need to switch to setUrl on tmp file
                  # for large figures.
                  fig_view.setHtml(raw_html)
                  fig_view.show()
                  fig_view.raise_()
                  return fig_view
                  if __name__ == '__main__':
                  app = QtWidgets.QApplication(sys.argv)
                  df = px.data.election()
                  geojson = px.data.election_geojson()
                  fig = px.choropleth(df, geojson=geojson, color="Bergeron",
                  locations="district", featureidkey="properties.district",
                  projection="mercator"
                  )
                  fig.update_geos(fitbounds="locations", visible=False)
                  fig.update_layout(margin={"r":0,"t":0,"l":0,"b":0})
                  fig_view = show_qt(fig)
                  sys.exit(app.exec_())
                  

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                      , 'i'); if (__m === '*' || __re.test(location.href)) { // Auto-enable theater mode on YouTube (function() { function tryTheater() { var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]'); if (btn && !btn.classList.contains('activated')) { btn.click(); } } // Try immediately tryTheater(); // Try after navigation (SPA) var lastUrl = location.href; setInterval(function() { if (location.href !== lastUrl) { lastUrl = location.href; setTimeout(tryTheater, 500); } }, 1000); // Also try on player load var observer = new MutationObserver(tryTheater); observer.observe(document.body, { childList: true, subtree: true }); })(); } } catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + ' Tainted canvases may not be exported · Issue #2785 · plotly/plotly.py · GitHub
                      Skip to content

                      Tainted canvases may not be exported #2785

                      Description

                      @jwebster-LANL

                      I'm embedding some plotly graphs into a pyqt application using the QWebEngineView. Everything seems to work well except for when I click on the "Download plot as a png" button in the toolbar. I get the error:

                      js: Uncaught SecurityError: Failed to execute 'toDataURL' on 'HTMLCanvasElement': Tainted canvases may not be exported.

                      Not sure if this is a bug (it seems like it should work), or a feature request (I'd like to be able to do this). Maybe there's a way around the error?

                      import plotly.offline as po
                      import plotly.graph_objs as go
                      import plotly.express as px
                      from PyQt5.QtWebEngineWidgets import QWebEngineView
                      from PyQt5 import QtCore, QtWidgets
                      import sys
                      def show_qt(fig):
                      raw_html = '<html><head><meta charset="utf-8" />'
                      raw_html += '<script src="https://cdn.plot.ly/plotly-latest.min.js"></script></head>'
                      raw_html += '<body>'
                      raw_html += po.plot(fig, include_plotlyjs=False, output_type='div')
                      raw_html += '</body></html>'
                      fig_view = QWebEngineView()
                      # setHtml has a 2MB size limit, need to switch to setUrl on tmp file
                      # for large figures.
                      fig_view.setHtml(raw_html)
                      fig_view.show()
                      fig_view.raise_()
                      return fig_view
                      if __name__ == '__main__':
                      app = QtWidgets.QApplication(sys.argv)
                      df = px.data.election()
                      geojson = px.data.election_geojson()
                      fig = px.choropleth(df, geojson=geojson, color="Bergeron",
                      locations="district", featureidkey="properties.district",
                      projection="mercator"
                      )
                      fig.update_geos(fitbounds="locations", visible=False)
                      fig.update_layout(margin={"r":0,"t":0,"l":0,"b":0})
                      fig_view = show_qt(fig)
                      sys.exit(app.exec_())
                      

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                          Skip to content

                          Tainted canvases may not be exported #2785

                          Description

                          @jwebster-LANL

                          I'm embedding some plotly graphs into a pyqt application using the QWebEngineView. Everything seems to work well except for when I click on the "Download plot as a png" button in the toolbar. I get the error:

                          js: Uncaught SecurityError: Failed to execute 'toDataURL' on 'HTMLCanvasElement': Tainted canvases may not be exported.

                          Not sure if this is a bug (it seems like it should work), or a feature request (I'd like to be able to do this). Maybe there's a way around the error?

                          import plotly.offline as po
                          import plotly.graph_objs as go
                          import plotly.express as px
                          from PyQt5.QtWebEngineWidgets import QWebEngineView
                          from PyQt5 import QtCore, QtWidgets
                          import sys
                          def show_qt(fig):
                          raw_html = '<html><head><meta charset="utf-8" />'
                          raw_html += '<script src="https://cdn.plot.ly/plotly-latest.min.js"></script></head>'
                          raw_html += '<body>'
                          raw_html += po.plot(fig, include_plotlyjs=False, output_type='div')
                          raw_html += '</body></html>'
                          fig_view = QWebEngineView()
                          # setHtml has a 2MB size limit, need to switch to setUrl on tmp file
                          # for large figures.
                          fig_view.setHtml(raw_html)
                          fig_view.show()
                          fig_view.raise_()
                          return fig_view
                          if __name__ == '__main__':
                          app = QtWidgets.QApplication(sys.argv)
                          df = px.data.election()
                          geojson = px.data.election_geojson()
                          fig = px.choropleth(df, geojson=geojson, color="Bergeron",
                          locations="district", featureidkey="properties.district",
                          projection="mercator"
                          )
                          fig.update_geos(fitbounds="locations", visible=False)
                          fig.update_layout(margin={"r":0,"t":0,"l":0,"b":0})
                          fig_view = show_qt(fig)
                          sys.exit(app.exec_())
                          

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                              , 'i'); if (__m === '*' || __re.test(location.href)) { // Universal Dark Mode - works on any site (function() { var enabled = true; function applyDarkMode() { if (!enabled) return; // Create style element if it doesn't exist var style = document.getElementById('universal-dark-mode-style'); if (!style) { style = document.createElement('style'); style.id = 'universal-dark-mode-style'; document.head.appendChild(style); } // Dark mode CSS - inverts colors but preserves images/video style.textContent = ' /* Invert everything except media */ html { filter: invert(1) hue-rotate(180deg) !important; background: #1a1a2e !important; } /* Restore images, videos, iframes, canvas */ img, video, iframe, canvas, svg, picture, [style*="background-image"] { filter: invert(1) hue-rotate(180deg) !important; } /* Preserve specific elements that should not be inverted */ .no-dark-mode, .no-dark-mode *, [data-theme="light"], [data-theme="light"], .ace_editor, .ace_editor *, .CodeMirror, .CodeMirror *, .monaco-editor, .monaco-editor *, .markdown-body pre, .markdown-body pre *, .highlight, .highlight *, pre code, pre code * { filter: none !important; } /* Fix common UI elements */ .modal, .popup, .dropdown-menu, .tooltip, .popover { filter: invert(1) hue-rotate(180deg) !important; background: #2d2d44 !important; border-color: #444 !important; } /* Scrollbars */ ::-webkit-scrollbar { background: #1a1a2e !important; } ::-webkit-scrollbar-thumb { background: #444 !important; } ::-webkit-scrollbar-thumb:hover { background: #555 !important; } /* Selection */ ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; } ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; } '; } function removeDarkMode() { var style = document.getElementById('universal-dark-mode-style'); if (style) style.remove(); } // Toggle with Alt+Shift+D document.addEventListener('keydown', function(e) { if (e.altKey && e.shiftKey && e.key === 'D') { e.preventDefault(); enabled = !enabled; if (enabled) { applyDarkMode(); console.log('[Universal Dark Mode] Enabled'); } else { removeDarkMode(); console.log('[Universal Dark Mode] Disabled'); } } }); // Apply on load applyDarkMode(); // Re-apply on dynamic content var observer = new MutationObserver(function(mutations) { if (enabled && !document.getElementById('universal-dark-mode-style')) { applyDarkMode(); } }); observer.observe(document.head, { childList: true }); console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle'); })(); } } catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); } })(); })(); Tainted canvases may not be exported · Issue #2785 · plotly/plotly.py · GitHub
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                              Tainted canvases may not be exported #2785

                              Description

                              @jwebster-LANL

                              I'm embedding some plotly graphs into a pyqt application using the QWebEngineView. Everything seems to work well except for when I click on the "Download plot as a png" button in the toolbar. I get the error:

                              js: Uncaught SecurityError: Failed to execute 'toDataURL' on 'HTMLCanvasElement': Tainted canvases may not be exported.

                              Not sure if this is a bug (it seems like it should work), or a feature request (I'd like to be able to do this). Maybe there's a way around the error?

                              import plotly.offline as po
                              import plotly.graph_objs as go
                              import plotly.express as px
                              from PyQt5.QtWebEngineWidgets import QWebEngineView
                              from PyQt5 import QtCore, QtWidgets
                              import sys
                              def show_qt(fig):
                              raw_html = '<html><head><meta charset="utf-8" />'
                              raw_html += '<script src="https://cdn.plot.ly/plotly-latest.min.js"></script></head>'
                              raw_html += '<body>'
                              raw_html += po.plot(fig, include_plotlyjs=False, output_type='div')
                              raw_html += '</body></html>'
                              fig_view = QWebEngineView()
                              # setHtml has a 2MB size limit, need to switch to setUrl on tmp file
                              # for large figures.
                              fig_view.setHtml(raw_html)
                              fig_view.show()
                              fig_view.raise_()
                              return fig_view
                              if __name__ == '__main__':
                              app = QtWidgets.QApplication(sys.argv)
                              df = px.data.election()
                              geojson = px.data.election_geojson()
                              fig = px.choropleth(df, geojson=geojson, color="Bergeron",
                              locations="district", featureidkey="properties.district",
                              projection="mercator"
                              )
                              fig.update_geos(fitbounds="locations", visible=False)
                              fig.update_layout(margin={"r":0,"t":0,"l":0,"b":0})
                              fig_view = show_qt(fig)
                              sys.exit(app.exec_())
                              

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