Hi,
Not a solution in itself but a bit of explanation regarding this list of CEP HTML engines if you are not used to them. Adobe CEP stands for "Common Extensibility Platform" and let developers create extensions based on the Chromium Framework (or in english, extensions are HTML-based plugins).
The caveat is that for every extension, a chromium instance is added. They may be native panels that rely on CEP or you may have installed yourself some extensions, hence the list that you observe.
A last word is that CEP will be deprecated at some time and you should no longer see such a list. I understand my post won't be that helpful but at least you know why.
Hoping I didn't explain something you already knew.
Loic