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FREE & OPEN SOURCE Million Dollar Script is a free WordPress plugin for sponsor walls, campaign grids, fundraiser boards, and premium add-on workflows.

Legacy support, updated

Compare and merge changed files with WinMerge

WinMerge shows related files side by side and groups changed lines into differences. Work from backups, label each side carefully, and merge only reviewed changes into a separate working copy.

Applies to
Windows file comparison and carefully reviewed legacy customizations
Reviewed
First published

Prepare safe copies

  1. Back up the original files and confirm that you can restore them.
  2. Create a separate working copy for the merge. Do not experiment directly on a live website or the only copy of a customized file.
  3. Label the old customized file and the clean updated file so the left and right sides cannot be confused.

Compare and review

  1. In WinMerge, choose File > Open and select the two files or folders.
  2. Make the source side read-only when it must not be changed.
  3. Use Next Difference and Previous Difference to review each changed block in context.
  4. Copy only the intended difference in the correct direction. Recheck the destination pane after every merge.

Save and validate

  • Save the merged working copy under version control or with a clear backup trail.
  • Run the syntax, unit, or application checks that cover the changed file.
  • Deploy through the normal release process and keep the original backup until the result is verified.
  • For recurring changes, move the customization into supported hooks, templates, or an extension so future updates do not require manual core merges.