This fixes block headers overlapping over text in the buffer when using
a custom line height of 1.25.
It fixes the issue by making the parent container a v-flex,
vertically-justifying the content and moving from relative padding to
absolute padding for the header itself.
## Before/After
With setting:
```json
"buffer_line_height": {
"custom": 1.25
},
```
### Before
### After
### Release notes
Release Notes:
- Fixed headers in multi-buffers overlapping over content of the buffer
Thorsten Ball
3d041f4e91