[Accessibility]The contrast between foreground and background colors doesn't meet contrast ratio thresholds

[plabanTest1]

Accessibility tools used: Lighthouse & axe DevTools

Ensure the contrast between foreground and background colors meets the minimum contrast ratio thresholds.

Below are the elements with the contrast issue.

• project-title-input_title-field_en5Gd
• menu-bar_account-nav-menu_3uu9p > span

• react-tabs-2 > span

• react-tabs-4 > span

[gonfunko]

These are all part of Scratch's UI (not the blocks editor) and out of scope for this effort.