Knowledge row type 'Header' disappears when using Next ExperienceDescriptionKnowledge row type 'Header' disappears when using NX. The the table header is expected to show with a blue background with the white text 'Steps' and 'Information' when Polaris is enabled.Steps to Reproduce 1. Format a knowledge article header or body html with a blue background, displaying the white text 'Steps' and 'Information', for example: <table class="table frame-all" style="height: 177px; width: 100%;"><thead class="thead"><tr style="background-color: #27348b;"><th class="entry colsep-1 rowsep-1" style="height: 50px; width: 10%;"><strong><span style="color: #ffffff;">Steps</span></strong></th><th class="entry colsep-1 rowsep-1" style="height: 50px; width: 90%;"><strong><span style="color: #ffffff;">Information</span></strong></th></tr></thead> 2. In the same browser and using the same account, click settings and then switch the 'Turn On Next Experience' system property glide.ui.polaris.experience to true.3. Navigate to the same article and you will see that the table heading text disappears.4. Highlight the text between the heading and the table text and you will see that the table header text still exists, but is now just white tex displayed on a white background.WorkaroundThis is expected behaviour by the current design. The TH needs a background color due to the sticky headers. For the custom code described above, the fix is to move the inline background color from the TR to the TH: <table class="table frame-all" style="height: 177px; width: 100%;"><thead class="thead"><tr><th class="entry colsep-1 rowsep-1" style="height: 50px; width: 10%; background-color: #27348b;"><strong><span style="color: #ffffff;">Steps</span></strong></th><th class="entry colsep-1 rowsep-1" style="height: 50px; width: 90%; background-color: #27348b;"><strong><span style="color: #ffffff;">Information</span></strong></th></tr></thead>Related Problem: PRB1642203