ID 522687 - Switching Blending modes is slower while using Automatic Compilation Mode compared to Dynamic

Problem summary
Switching Blending modes is slower while using Automatic Compilation Mode compared to Dynamic
 
Customer reported version
Mari 5.0v4
 
Customer reported platform
CentOS 7
 
Steps to reproduce
 
1) Open any project
 
2) In Preferences > GPU > Shaders, switch Compilation Mode to "Automatic" (the default)

2) Select the Paint tool

3) Switch between "Normal" and "Clear" paint blending modes multiple times
 
4) Switch Compilation Mode to "Dynamic"
 
5) Switch between "Normal" and "Clear" paint blending modes multiple times, comparing the performance to Automatic Shader Compilation mode
 
Expected behaviour
The performance should be similar.
 
Actual behaviour
Switching Blend mode is slower (3-5s compared to instant) while using Automatic Shader Compilation Mode.
 
Workaround
Unknown.
 
Reproduced by support
This bug has been reproduced in:
Mari 5.0v4 - Windows 10 - CentOS 7.9
Mari 3.4v1 - Windows 10 - CentOS 7.9
 
Earliest version tested
Mari 3.4v1 - This feature did not exist before this version