Hostsite (hosts.php?form=update) freezes with 4500 Usermacros

Hello,

we have a problem with loading the MacroTab from the Hostpage. The Browser stalls and is asking to terminate the tab. 
Also updating the host is impossible in the UI. 

Steps to reproduce:

1. fill host with a lot of usermacros with API usermacro.create
2. Navigate to Host 
3. Click on screen element Macro
4. Wait forever...

Guess:

The MacroTab tries to load all usermacros within the same page and the database struggels to get the data. To load 5000 items is not a problem for zabbix because only 50 rows are loaded at the same time.