If you cannot reproduce on stable, try the latest canary or dev build.

can reproduce this issue since 73.0.3635.0 (Official Build), v72 works fine.

Tried to reproduce the issue on reported chrome version 73.0.3668.0 using Windows 10.Attaching screen-cast for reference.
Steps: 
-------
1. Launched reported chrome 
2. Enabled uBlock Origin
3. Opened chrome-extension://cjpalhdlnbpafiamejdnhcphjbkeiagm/dashboard.html#1p-filters.html
As we not observed add option in the Myfilters 

@Reporter: Could you please check the attached screencast and let us know if we missed anything form our end and if possible provide screencast for better understanding of this issue.

Thanks.!

Deleted: 920531.mp4 1.5 MB

	920531.mp4 1.5 MB View Download

Seems I wasn't clear before. Copy ||myanimelist.net^$csp=default-src 'self' 'unsafe-inline' 'unsafe-eval' cdn.myanimelist.net and paste it in My Filters and click on Apply changes, then close that page. Then follow onwards to step No. 2. 

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For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Just to add some clarification, In step 3, once the recorded network tab activity is populated, look for a network request to https://ads.rubiconproject.com/ad/13138.js and check its "Status", which will show "blocked:other" instead of blocked:csp, which shouldn't have happened because the CSP filter which we added in step 1 doesn't whitelist ads.rubiconproject.com and yet it wasn't blocked by CSP.

As per comment #5 and comment #7, retried the issue on reported chrome version 73.0.3668.0 using Windows 10.Attaching screen-cast for reference.
Steps: 
------
1. Launched reported chrome 
2. Copied and pasted the code link and opened Devtootls > Network tab 
3. Opened https://ads.rubiconproject.com/ad/13138.js 
As we have observed that the page is blocked by uBlock Origin 

@Reporter: Could you please check the attached screencast and confirm the issue and if possible provide screencast for better triaging of this issue.

Thanks.!

Deleted: 920531.mp4 9.4 MB

	920531.mp4 9.4 MB View Download

-Sigh-, somehow myanimelist.net domain is whitelisted in your screenshot, please remove that whitelisted entry from uBO from chrome-extension://cgbcahbpdhpcegmbfconppldiemgcoii/dashboard.html#whitelist.html and deleting the entry and clicking apply changes, otherwise uBO cannot do anything if the domain is whitelisted like that.

@ woxxom@gmail.com Can you please help ? 

Thank you for providing more feedback. Adding the requester to the cc list.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

@ phanindra.mandapaka@chromium.org see the screencast I have attached.

The request is blocked, but NOT blocked by CSP we added in My Filters, that's the issue. Do you understand now ?

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	9236afcfdde73c20ec37163899ff63fa.mp4 153 KB View Download

@ karandeepb@chromium.org please take a look into this.