I'm the maintainer of 'Expression Search/GmailUI'.
klint said "Because I have noted that we the TB default "Global Search" field is not displayed on any bar, pressing Shift+Enter on a criteria in ExpressionSearch field does not launch the search at all. On the contrary, when I add the "Global search" field to the top bar, then pressing Shift+Enter works correctly."
The reason it's conflict with 'Expression Search/GmailUI' is because this addon expect the element 'searchaslist-indicator' was show when gloda was launched, but it's not true if gloda was launched NOT by the gloda search box. In such case, you will get error
"Error: document.getElementById(...) is null
Source file: chrome://search-as-list/content/overlay.js
I've just started using your 'Expression Search/GmailUI' and it is excellent.
Thank you for clarifying this matter for me. In the next release I've fixed the indicator so that it will show up within the active search element (input).
Too many permutations.
Thanks again for your help.