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e.g. Maven Wagon is used by Maven Core and the Maven Site pluginPlugin. If
- the Core development line is 4.5 and depends on Wagon 5.7,
- the Core maintenance line(s) are 4.4 and 3.7 depending on Wagon 5.6 and 5.5 respectively,
- the Site Plugin development line is 6.2 depending on Wagon 5.5 and
- the Site maintenance Plugin maintenance line is 6.1 depending on Wagon 5.4
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- Wagon 5.8 is the development line
- Wagon 5.7 is a maintenance line (as Core is the corresponding development line)
- Wagon 5.6 is a maintenance line (as Core has a maintenance line)
- Wagon 5.5 is a maintenance line (as Core has a maintenance line and Site has Plugin has a development line)
- Wagon 5.4 is a maintenance line (as Site has Plugin has a development line)
If a bug fix to Site 6Plugin 6.1 requires an upgrade of Wagon from the 5.4 line then that bug fix is out of scope for back-porting. The only changes to Site Plugin's 6.1.x dependency on Wagon must stay in the range [5.4,5.5) as moving out of this range would represent an increase in functionality and is thus out of scope for a maintenance line.
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