We want to inform the community of a significant issue that affects clients using Skuid on Salesforce in Lightning App Builder pages. 

History
As soon as Summer '18 pre-release orgs were available, Skuid began testing. As soon as we became aware of this issue in the pre-release org, Skuid reported to Salesforce that Skuid pages displaying within Lightning App Builder pages do not load and result in this error message in the console: 

• Error: Invalid XML: LYour Page’s XML]

The case was escalated to Salesforce’s R&D and they have been working on a fix for this issue. 

Skuid’s product engineers have also looked into this issue and are, unfortunately, unable to provide a workaround for this issue. 

All preview instance sandboxes (check here to see if you are on a preview or non preview sandbox instance) were upgraded to Summer '18 on May 4th and 5th. 

What Does this mean to Me? 
I use Skuid on Lightning using VisualForce overrides:

• You should NOT experience any issues. If you are, please let us know!!! 

 I use Skuid on Lightning using Lightning App Builder pages: 

• You ARE affected by this issue whether you use standard Lightning App Builder pages, Lightning Community pages, … 


• Until Salesforce resolves this issue, you can spin up a new sandbox as any sandbox requests submitted after noon PST on May 4, 2018 should be set to a Non-Preview Instance. 

We are continuing to be in communication with Salesforce about how to expedite resolution of this issue. We have heard that the fix is coming soon and will update the community when more information becomes available. 

Thank you for your patience and understanding.
Karen