[wp-trac] [WordPress Trac] #43166: 4.9 broke uploaded images' paths on my network installation

[WordPress Trac]

#43166: 4.9 broke uploaded images' paths on my network installation
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 Reporter:  pasqal        |      Owner:
     Type:  defect (bug)  |     Status:  new
 Priority:  normal        |  Milestone:  Awaiting Review
Component:  General       |    Version:  4.9
 Severity:  normal        |   Keywords:
  Focuses:  multisite     |
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 I run a network installation. I upgraded from 4.8.2 to 4.9 back in
 December but found out that images were broken on all of my network's
 sites.

 My network's sites are as follows:

 Site 1: https://www.mybrand.com/es/blog/
 Site 2: https://www.mybrand.com/en/blog/
 Site 3: https://www.mybrand.co.uk/en/blog/
 Site 4: https://www.mybrand.it/it/blog/
 etc.

 4.9 converts a 4.8.2 working image URL on Site 1, such as:
 https://www.mybrand.com/es/blog/wp-
 content/uploads/sites/1/2016/09/image.jpg

 ...into the following non-existent URL:
 https://www.mybrand.com/es/blog/wp-content/uploads/2016/09/image.jpg

 ... thus resulting in a 404 response for the image load.

 Since I had upgraded some plugins together with the Wordpress core, what I
 tried first was deactivating those, with no success. So I ended up
 downgrading the core back to 4.8.2, which fixed the bug.

 Last week I again tried upgrading to 4.9.2, with the same result (the
 image bug is still there). This time I downgraded to 4.8.5, which works
 fine.

 All sites use the Twenty Sixteen template.

 My current install includes the following plugins at the network level:
 * AddToAny Share Buttons Version 1.7.23
 * All In One SEO Pack Version 2.4.4.1
 * Autoptimize Version 2.3.2
 * Broken Link Checker Version 1.11.5
 * Custom Meta Widget Version 1.4.8
 * Custom Permalinks Version 1.2.12
 * Customize Login Image Version 3.3.1
 * Disable REST API Version 1.4.2
 * External Links Version 6.8.1
 * Google Analytics for WordPress by MonsterInsights Version 6.2.7
 * Google Captcha (reCAPTCHA) by BestWebSoft Version 1.33
 * HREFLANG Tags Lite Version 1.5.6 | By DCGWS
 * Jetpack by WordPress.com Version 5.7.1
 * kk Star Ratings Version 2.6
 * Simple 301 Redirects Version 1.07
 * W3 Total Cache Version 0.9.6
 * wBounce Version 1.8
 * WordPress Importer Version 0.6.3
 * WP Downgrade Version 1.1.4
 * WP Login Flow Version 1.0.0
 * WP Rollback Version 1.5

 I actually installed WP Downgrade and WP Rollback after 4.9 broke my
 installation, to help downgrade to a working version.

 All templates and plugins are up to date.

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Ticket URL: <https://core.trac.wordpress.org/ticket/43166>
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