Broken image placeholders.
THE COMMON CAUSES
URLs in the database still pointing at an old domain, after a migration Mixed content, where images are requested over http on an https page The files are genuinely missing Permissions wrong A caching or optimisation plugin failing
DIAGNOSING
Right-click a broken image and open it in a new tab. The error tells you which:
404: the file is missing, or the path is wrong 403: permissions
Mixed content warning in the console: scheme problem
AFTER A MIGRATION
Run a database search and replace from the old URL to the new one. Use a tool that handles serialised data.
Check the uploads directory actually transferred. Media is frequently the largest part and the part that fails during transfer.
MIXED CONTENT
Search and replace http://yourdomain.com with the https form.
PERMISSIONS
Directories 755, files 644. Check ownership too.
OPTIMISATION PLUGINS
Some serve images from a cache or a rewritten URL. Disable the plugin temporarily to test.
CHECKING WHAT THE PAGE REQUESTS
The Network tab shows the exact URL being requested, which usually makes the cause obvious.
