Comparing two versions of a test or flow is now easier to read, whether you're on a branch, browsing version history, or resolving a merge conflict. We've made several improvements to how mabl shows what changed between versions and make sure real edits stand out.
No action is required for the in-app improvements below; they're already in effect wherever you compare versions or resolve conflicts.
Moved steps no longer read as deleted and re-added
mabl now matches steps between versions by their step ID, so a step that moved keeps its place in the comparison instead of showing up as a deletion and a re-addition. For example, when you wrap existing steps in a step group, those steps show as unchanged with a new group around them, rather than every step reading as removed and re-added.
Side-by-side comparisons also line up row by row. When a step renders taller on one side, its counterpart stays inline across from it instead of drifting down the column, so you can read a change against its before and after.
More details on visual assertions
Visual assertion steps now include an AI assertion details section in the diff, listing the assertion's prompt and each criterion, the same way find and target details already appear. If the prompt or a criterion changed between versions, you can see it side by side.
Previously, the diff showed no prompt or criteria for visual assertions, so editing what an assertion checked left the two versions looking identical even when the behavior had changed.
Step groups render correctly in diffs
Step groups now display and expand cleanly when you compare versions. Nested steps appear under their group, and expanding a group on one side expands its counterpart on the other, so both columns stay in sync as you drill in.
Compare versions from the mabl MCP server
Agents and tools connected through the mabl MCP server can now compare test and flow versions directly. Two new tools, mabl_compare_test_versions and mabl_compare_flow_versions, return the same step-level diff the web app shows: each step marked added, removed, changed, or unchanged, with before and after details. You can also point them at specific historical versions to compare.