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If not, please describe it

Upload max filesize
Instead of php.ini, each administrator (or operator) would have to decide upload_max_filesize = 5M
Add an option in GLPI to set the "upload_max_filesize = " instead of php.ini

Sessions expire
Instead of php.ini and httpd.conf, each administrator (or operator) would have to decide how long the GLPI should be inactivated from your session: now we are going to do a 10-minute troubleshooting, We return, the session closes.
Add an option in GLPI to set the session expire instead of php.ini and httpd.conf
You could even configure the message, "Your session has expired" in the login page, once it is redirected to the login page.

Split solution description in 2
Split a solution in two fields :
- solution for the user (in general a short text)
- technical solution : a link to a KB article
If a KB article is created from a solution, link the solution to the article.

Disable notifications for user's own changes/Followups when made by e-mail. GLPI 9.1.2
I noticed, that when I simulate a client and send a email followup, I get a "copy" response of my own followup to my email.
I've seen several users displeased by this topic.

Possibility to add a group as watcher on the simplified interface
Possibility to add a group as watcher on the simplified interface, at the moment is possible to do it only in the standard interface

Business rules: add validation state in criterias
It would be nice to have added the criteria "validation state" in the ticket business rules.
This way, when a validation is needed, I could set a rule freezing the SLA until the ticket goes back to the treating service.
thnks

Please! An important suggestion to add the status
Please add the status of "approval" for ticket that appears automatically at the time of the request for validation, as new and processing (assigned) and Solved, etc.Please, very need!

Model the uninterruptible power supply (UPS) and what they are powering
I think it would be useful to model the fact a computer or network equipment (and maybe other asset types) is powered by a given UPS (helps for power outages).
I'm not asking to create new assets types for UPS (I am using peripheral for that) but being able to link a single peripheral to multiple computer (which is not possible at the moment, it can only be linked to one computer) and/or to multiple network equipments (it's currently not possible to link peripherals to anything other than a computer).

tasks chain
When a ticket has several tasks to do, you can add the ability to link between them in order to see the tracking of the resolution ?

Timezone Plugin integration
Plain simple. Having users in different timezones is not easy without this plugin.
Let's add it to the core.
https://github.com/tomolimo/timezones
By the way thanks Tomolino.
Customer support service by UserEcho