Wrong comparison between Web Content versions when there are one or more tags img without attribute src

• Type: Bug
• Status: Closed
• Resolution: Fixed
• Affects Version/s: 7.0.X, 7.1.X, 7.2.X, 7.3.X, Master
• Fix Version/s: 7.0.0 DXP FP97, 7.0.X, 7.1.10 DXP FP21, 7.1.X, 7.2.10 DXP FP10, 7.2.10.4 DXP SP4, 7.2.X, 7.3.10 DXP FP1, 7.3.10.1 DXP SP1, 7.3.6 CE GA7, 7.3.X, 7.4.13 DXP GA1, Master
• Component/s: Web Content > Web Content Administration
• Labels:
  • ee-ts
  • liferay-dxp-72-sp4
  • liferay-dxp-73-sp1
  • liferay-fixpack-de-97-7010
  • liferay-fixpack-dxp-1-7310
  • liferay-fixpack-dxp-10-7210
  • liferay-fixpack-dxp-21-7110
• Branch Version/s:
  7.3.x, 7.2.x, 7.1.x, 7.0.x
• Backported to Branch:
  Committed
• Fix Priority: 3
• Git Pull Request: https://github.com/liferay-echo/liferay-portal/pull/3009

Steps to reproduce:

1. Create a new Structure with a text field with name textField1
2. Create a new Template for the previous Structure like <img alt="Image" />${textField1.getData()}
3. Create a new Web Content WC1 based off of the Structure created previously
4. Modify the Web Content and create a new version
5. Compare the two versions

Expected result:

• The differences between the two versions are shown

Actual result:

• The differences between the two versions are not shown
• The following error is displayed in server logs:

  SystemId Unknown; Line #1; Column #4; java.lang.NullPointerException