No,Category,Issue,Keywords,Platform,Description,Do,Don't,Code Example Good,Code Example Bad,Severity
1,Accessibility,Icon Button Labels,icon button aria-label,Web,Icon-only buttons must have accessible names,Add aria-label to icon buttons,Icon button without label,"<button aria-label='Close'><XIcon /></button>","<button><XIcon /></button>",Critical
2,Accessibility,Form Control Labels,form input label aria,Web,All form controls need labels or aria-label,Use label element or aria-label,Input without accessible name,"<label for='email'>Email</label><input id='email' />","<input placeholder='Email' />",Critical
3,Accessibility,Keyboard Handlers,keyboard onclick onkeydown,Web,Interactive elements must support keyboard interaction,Add onKeyDown alongside onClick,Click-only interaction,"<div onClick={fn} onKeyDown={fn} tabIndex={0}>","<div onClick={fn}>",High
4,Accessibility,Semantic HTML,semantic button a label,Web,Use semantic HTML before ARIA attributes,Use button/a/label elements,Div with role attribute,"<button onClick={fn}>Submit</button>","<div role='button' onClick={fn}>Submit</div>",High
5,Accessibility,Aria Live,aria-live polite async,Web,Async updates need aria-live for screen readers,Add aria-live='polite' for dynamic content,Silent async updates,"<div aria-live='polite'>{status}</div>","<div>{status}</div> // no announcement",Medium
6,Accessibility,Decorative Icons,aria-hidden decorative icon,Web,Decorative icons should be hidden from screen readers,Add aria-hidden='true' to decorative icons,Decorative icon announced,"<Icon aria-hidden='true' />","<Icon /> // announced as 'image'",Medium
7,Focus,Visible Focus States,focus-visible outline ring,Web,All interactive elements need visible focus states,Use :focus-visible with ring/outline,No focus indication,"focus-visible:ring-2 focus-visible:ring-blue-500","outline-none // no replacement",Critical
8,Focus,Never Remove Outline,outline-none focus replacement,Web,Never remove outline without providing replacement,Replace outline with visible alternative,Remove outline completely,"focus:outline-none focus:ring-2","focus:outline-none // nothing else",Critical
9,Focus,Checkbox Radio Hit Target,checkbox radio label target,Web,Checkbox/radio must share hit target with label,Wrap input and label together,Separate tiny checkbox,"<label class='flex gap-2'><input type='checkbox' /><span>Option</span></label>","<input type='checkbox' id='x' /><label for='x'>Option</label>",Medium
10,Forms,Autocomplete Attribute,autocomplete input form,Web,Inputs need autocomplete attribute for autofill,Add appropriate autocomplete value,Missing autocomplete,"<input autocomplete='email' type='email' />","<input type='email' />",High
11,Forms,Semantic Input Types,input type email tel url,Web,Use semantic input type attributes,Use email/tel/url/number types,text type for everything,"<input type='email' />","<input type='text' /> // for email",Medium
12,Forms,Never Block Paste,paste onpaste password,Web,Never prevent paste functionality,Allow paste on all inputs,Block paste on password/code,"<input type='password' />","<input onPaste={e => e.preventDefault()} />",High
13,Forms,Spellcheck Disable,spellcheck email code,Web,Disable spellcheck on emails and codes,Set spellcheck='false' on codes,Spellcheck on technical input,"<input spellCheck='false' type='email' />","<input type='email' /> // red squiggles",Low
14,Forms,Submit Button Enabled,submit button disabled loading,Web,Keep submit enabled and show spinner during requests,Show loading spinner keep enabled,Disable button during submit,"<button>{loading ? <Spinner /> : 'Submit'}</button>","<button disabled={loading}>Submit</button>",Medium
15,Forms,Inline Errors,error message inline focus,Web,Show error messages inline near the problem field,Inline error with focus on first error,Single error at top,"<input /><span class='text-red-500'>{error}</span>","<div class='error'>{allErrors}</div> // at top",High
16,Performance,Virtualize Lists,virtualize list 50 items,Web,Virtualize lists exceeding 50 items,Use virtual list for large datasets,Render all items,"<VirtualList items={items} />","items.map(item => <Item />)",High
17,Performance,Avoid Layout Reads,layout read render getboundingclientrect,Web,Avoid layout reads during render phase,Read layout in effects or callbacks,getBoundingClientRect in render,"useEffect(() => { el.getBoundingClientRect() })","const rect = el.getBoundingClientRect() // in render",Medium
18,Performance,Batch DOM Operations,batch dom write read,Web,Group DOM operations to minimize reflows,Batch writes then reads,Interleave reads and writes,"writes.forEach(w => w()); reads.forEach(r => r())","write(); read(); write(); read(); // thrashing",Medium
19,Performance,Preconnect CDN,preconnect link cdn,Web,Add preconnect links for CDN domains,Preconnect to known domains,"<link rel='preconnect' href='https://cdn.example.com' />","// no preconnect hint",Low
20,Performance,Lazy Load Images,lazy loading image below-fold,Web,Lazy-load images below the fold,Use loading='lazy' for below-fold images,Load all images eagerly,"<img loading='lazy' src='...' />","<img src='...' /> // above fold only",Medium
21,State,URL Reflects State,url state query params,Web,URL should reflect current UI state,Sync filters/tabs/pagination to URL,State only in memory,"?tab=settings&page=2","useState only // lost on refresh",High
22,State,Deep Linking,deep link stateful component,Web,Stateful components should support deep-linking,Enable sharing current view via URL,No shareable state,"router.push({ query: { ...filters } })","setFilters(f) // not in URL",Medium
23,State,Confirm Destructive Actions,confirm destructive delete modal,Web,Destructive actions require confirmation,Show confirmation dialog before delete,Delete without confirmation,"if (confirm('Delete?')) delete()","onClick={delete} // no confirmation",High
24,Typography,Proper Unicode,unicode ellipsis quotes,Web,Use proper Unicode characters,Use ... curly quotes proper dashes,ASCII approximations,"'Hello...' with proper ellipsis","'Hello...' with three dots",Low
25,Typography,Text Overflow,truncate line-clamp overflow,Web,Handle text overflow properly,Use truncate/line-clamp/break-words,Text overflows container,"<p class='truncate'>Long text...</p>","<p>Long text...</p> // overflows",Medium
26,Typography,Non-Breaking Spaces,nbsp unit brand,Web,Use non-breaking spaces for units and brand names,Use &nbsp; between number and unit,"10&nbsp;kg or Next.js&nbsp;14","10 kg // may wrap",Low
27,Anti-Pattern,No Zoom Disable,viewport zoom disable,Web,Never disable zoom in viewport meta,Allow user zoom,"<meta name='viewport' content='width=device-width'>","<meta name='viewport' content='maximum-scale=1'>",Critical
28,Anti-Pattern,No Transition All,transition all specific,Web,Avoid transition: all - specify properties,Transition specific properties,transition: all,"transition-colors duration-200","transition-all duration-200",Medium
29,Anti-Pattern,Outline Replacement,outline-none ring focus,Web,Never use outline-none without replacement,Provide visible focus replacement,Remove outline with nothing,"focus:outline-none focus:ring-2 focus:ring-blue-500","focus:outline-none // alone",Critical
30,Anti-Pattern,No Hardcoded Dates,date format intl locale,Web,Use Intl for date/number formatting,Use Intl.DateTimeFormat,Hardcoded date format,"new Intl.DateTimeFormat('en').format(date)","date.toLocaleDateString() // or manual format",Medium
