This is a tool for finding and replacing text in expressions, layer names, property names (the ones that can be renamed) and text content. It can use javascript regular expressions to do the job, so you can do complex search and replaces, but regular ol’ find-foo-replace-with-bar will still work.
Teaching regular expressions is waaaay beyond the scope of this little blog, there are a ton of resources out there written by people who actually study this kind of thing. A starter is the mozilla documentation.

Targets
sets what will be searched and replaced. Note that some property names, like effect controls, can be changed while others can’t. The script will fail silently if the property name cannot be changed. If you change layer names the references to them in expressions are automatically updated.
Search Patterns
The regular expressions, or plain text that you want to search for, and then replace with, e.g. foo
and bar
or f([o]*)
and b$1r
Case-Insensitive
Search without considering case. E.g. foo
will match Foo
and FOO
Regex flags (for regex searches)
Global
Don’t give up after finding the first match. e.g. in the text foobarfoo
the search pattern foo
will match twice with global on, and once without.
Multi Line
Search patterns can include line breaks.
‘.’ matches newline
The period character .
normally matches any character except for newlines (line breaks). Turn this on and it will match them too.
Layer and Property filters
Choose whether to only search in selected layers or properties, and whether to apply changes to locked layers too.
Installing After Effects Scripts
Recent versions of After Effects will take care of the installation for you. For scripts with a UI, go to the File menu in AE and choose Scripts>Install Script UI Panel. Point it at the unzipped .jsx file that you just downloaded and let it work its magic, then restart AE.
Running the script
Once the script is installed it should appear in AE’s Window> menu. Calling the script from this menu will make its window appear, and it can then be docked like any other panel. If you want it to always be visible, add it to your workspace.
Download
You can download this script along with all my other scripts here. Or to download just this script click the download button below.
All the scripts – blob
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