As said, just change code a bit and stick with Megabytes (MB), so it is technically correct:
```python
cache.setMaximumCacheSize(config.setting["webcache_size_maximum"] * 1024 * 1024) 
```
to
```python
cache.setMaximumCacheSize(config.setting["webcache_size_maximum"] * 1000 * 1000)
```

MiB unit is part of IEC standard, this is a 15-years old story, nothing really new, the fact people don't know about it isn't really our problem, technically we have to use proper units, especially when those where accepted by all major standards organizations.