Titan Mail has an in-built 'Universal Contact List', this allows you to get the auto-completion of email suggestions from contacts of multiple email accounts you are logged in at the Web Client while entering the email address / term in the Composer :
Here is the use case in which this could be really handy :
Joshua, a marketing consultant has 2 accounts -
1) email@example.com, where he interacts mostly related to projects, queries, etc, and the other account.
2) firstname.lastname@example.org which he mostly uses for invoice-related stuff.
For escalations, he uses the email@example.com account but it doesn’t have all the invoice-related email addresses hence he has to copy-paste from another account. Universal Contact List solves this problem by providing prompts for email addresses from across accounts, when entering a recipient address in the 'To' field.
In the case of multi-account, we can show a max of up to 8 results in autosuggestion