WebUI improved usability to find a certain modification of a file
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### Release notes
Find the modification to a certain file in a certain commit by an improvement of coherence. Just stay with previous constraints when applicable.
### Problem to solve
Navigate to a file.
You see the current content.
Now you want to find out, what was changed in this file for a certain commit stepping through the commit history.
Press the History button.
Now you see the list of commits that modified the file.
Now click on the commit
**Now the context is gone**
If it is a big commit with many many files, you see only 20 of them perhaps on 30 pages, so most probably not the file you came from!
The "Showing 20 changed files" drop down list does not provide immediate access to the file you came from. Only the current 20 files are shown.
### Proposal
Different improvements could be made:
A) Keep the context: navigate to the file you came from when switching to a commit. So no additional search is necessary.
B) Allow the drop down box to search for all files of the commit, not only the shown files (browser search would help here already)
C) Create file filters for the commit view to only show relevant files
### Intended users
All
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### Feature Usage Metrics
Happiness
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