Erase parts of webpages.
Firstly, install into your browser an extension called 'TamperMonkey', or one called 'GreaseMonkey', these are userscript managers. You can find the extension at the chrome web store: https://chrome.google.com/webstore/detail/tampermonkey/dhdgffkkebhmkfjojejmpbldmpobfkfo, or at the firefox extensions website, https://addons.mozilla.org/en-US/firefox/addon/tampermonkey.
Secondly, install this script by clicking on the link: https://github.com/TerryCross/WebEraser/raw/main/WebEraser.user.js.
Below, at the end, you will find two screenshots of a typical website that uses large images.
The first screenshot shows an example page from stackoverflow after having used this script to erase the image.
The second screenshot shows the page as it normally appears without using this script.
After installing this script clicking on a browser webpage, on any advert/image/text etc., whilst holding down the "Ctrl" key, erases it by drawing curtains over it. Upon revisiting the page at another time, the advert/image etc. will still be erased. A double Click on an erased (curtained) space temporarily reveals that which was erased.
If clicking on the item tends to cause other effects such as opening a new tab or visiting another page, the the special menu option "Erase via mouse hover" can be invoked without having to click on the item.
The script also adds to the TamperMonkey (GreaseMonkey) menu a command that gives access to the scripts options. One of which allows one to set the 'curtain' image to a http image address or a base64 string. It also allows manual alteration of the selectors used to find elements for erasure. Another option allows for complete erasure of items leaving more space for other items on the page (for this, untick the "preserve layout" tickbox).
To access this script's options: ctrl-click anywhere, you should see a small popup, then click on link named 'Preferences...' that appears within the small popup.
Save this script by clicking the right mouse button upon the link mentioned above .../WebEraser.user.js, then choose "Save link as...". Then drag and drop the saved link from a file manager onto chrome's "extensions" page. Chrome's extensions page is accessible from the Chrome menu "More tools->Extensions.", also switch the top right "Developer mode" button to the "on" position and reload the page before drag-drop operation.
The script's menu is then accessible from any webpage in Chrome via the small 'Monkey' icon at the top right of any page.
WebEraser, Cover anything on the web with Weberaser.