Sometimes we need to change the limit the input number of allowed characters in any magento area.

Consider the example of overwriting an HTML file in the adminhtml. In this example, the max-length value of the text-box in the adminhtml is altered. The HTML file is located at vendor/magento/module_ui/view/base/web/templates/form/element/input.html.

Step1:

Create a requirejs-config.js file under app/code/Bluethink/InputField/view/base/ and add the following code:

Step2:

Create an input.html file under

app/code/Bluethink/InputField/view/base/web/template/form/element/ and copy the contents of the input.html file from the module_ui template file.

Step3:

Change the maxlength value to 512, which was originally set to 256.

Step 4:

bin/magento setup:upgrade

bin/magento setup:di:compile

Step 5:

Confirm the modification by inspecting the element source code and check the maxlength value, which should be 512 as specified in the template.