This doesn't seem like a bootstrap reaction problem, but rather a reaction. The reaction does not transfer the "readonly" prop to the generated (valid) DOM element:
React-bootstrap create the following dom virtual login response: 
However, the reaction generated the following real DOM element, omitting the readonly attribute: 
Perhaps using "disabled" might help in your case:
<FormControl disabled type="text" placeholder="Enter text" onChange={this.handleChange} />
For the differences between readonly and disbabled, see here: https://stackoverflow.com/a/16837/16937/ ...
I created a problem in the React github repo: # 6783
UPDATE
Having received the answer in the above problem. You need to write it using camelcase: readOnly.
So this should be:
<FormControl readOnly type="text" placeholder="Enter text" onChange={this.handleChange} />
omerts
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