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If not, please describe it

Custom Field in Simplified Interface
In version 9.1 would be very good to have this possibility, using a plugin or not.

Busines Rules: Add ID´s in list of criteria (itilcategories_id, locations_id, users_id)
Dear fellows,
I need create SLA rule for specific locations and categories, like this:
Criterion : Tickets Locations_ID IN (12, 455, 650, 660, 1200, 1300, 400, 1501)
Criterion : Tickets Categories_ID IN (45, 46, 47, 60, 61, 62, 63, 75, 74,76,77,90)
Actions : set Ticket Priority to High
Is possible?

Wiki plugin for documentation
The idea consist in adding a wiki plugin for documentation purposes

Delete project tasks
Add the possibility to delete project tasks and add permission to the profiles.

Private Documents
Can you please make a feature to allow documents to be made private in a ticket.
Every now and again we need to attach a documents to a ticket that contains private information.
As documents are not private we have been saving these documents into our departments shared network drive.
Not saving these documents to the ticket often causes issues if the case is reviewed at a later date.

automatic ticket transfer rule
Here is a good feature
Business rule to transfer tickets between entities. (new action - move to entity...)

Possibility to hide "Automatically generated by GLPI X.XX"

new searchtype REGEXP/RLIKE : match regular expression
Actually searchtypedropdowns are "contains, is, is not, less than, more than, under, not under"
in many case "match regular expression" would improve search and make selection criteria interface much easier.
select * from table where field regexp SomeregularExpression

Easy checkout/checkin for loaner asset
While you can use the GLPI reservations interface for immediate checkout/checkin of reservable assets, it is a bit cumbersome. I wrote a proposal, publicly available from my google disk (click link), for a simplified check-out/check-in solution. (I found it a bit lengthy to post in full here, and can't see any option to attach a file.)
An implementation of this functionality would simplify handling of loaner assets "over the counter", and also facilitates self service stations for registering loan/return.
Customer support service by UserEcho