The standard advice for a plugin conflict is to deactivate all plugins and reactivate them one by one until the problem returns. On a site with 20 or 30 plugins, that’s a long afternoon. Loupely often makes it unnecessary. The PHP error capture includes the file path of whatever code caused the failure, and that path almost always names the plugin. Run the diagnosis on the page or action that’s broken, read the triage output, and you have your target before touching a single plugin setting.
The cases where deactivation testing is still needed: silent failures with no PHP error (a plugin is doing something wrong that doesn’t throw an error, just produces incorrect behavior), JavaScript conflicts (two plugins loading incompatible scripts), or CSS conflicts (one plugin’s styles overriding another’s in ways that break layout). Loupely captures JavaScript errors too, so the extension popup is still a useful first stop before manual testing.
When you do need to isolate manually #
The Health Check and Troubleshooting plugin (free, WordPress.org) is the best tool for manual plugin conflict testing. Its troubleshooting mode activates for your admin session only. Visitors continue seeing the normal site while you test with all plugins deactivated, then reactivate them one by one. This is far better than bulk-deactivating from the plugins page, which takes the broken functionality down for everyone while you test.
If you have a large number of plugins and want to narrow the field faster, use binary search: split your plugins into two groups, activate one group and test, then narrow to whichever group contains the conflict. With 30 plugins, 5 rounds of testing finds the culprit instead of 30 individual tests.
After identifying the conflicting plugin #
Check whether an update is available for the plugin. Many conflicts are fixed in newer versions. If the developer knows about the conflict, the fix is often already there. If no update exists, check the plugin’s support forum on WordPress.org to see if others have hit the same conflict and whether there’s a workaround. If the plugin is actively maintained, opening a support ticket with the capture file from Loupely gives the developer the exact error context they need to reproduce and fix it. If the plugin hasn’t been updated in two or more years, it’s effectively abandoned, and finding a maintained alternative is the more reliable path than waiting for a fix that may never come.